Vegetable Production Handbook for Florida 2012-2013 EDITORS: Stephen M. Olson, Ph.D. Bielinski Santos, Ph.D. University of Floridas North Florida University of Floridas Gulf Coast Research and Education Center, Quincy Research and Education Center, WimaumaCitrus & Vegetable MA G A Z I N E
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Vegetable Production Handbook for Florida 2012-2013 Editors: Stephen M. Olson, Ph.D. Bielinski Santos, Ph.D. University of Floridas North Florida University of Floridas Gulf Coast Research and Education Center, Quincy Research and Education Center, WimaumaCitrus & Vegetable MA G A Z I N E
AUTHORS D aniel A. Botts, Director, Environmental and Pest Management Division, Florida Fruit & Vegetable Association - Maitland Peter J. Dittmar, Assistant Professor, Horticultural Sciences Department - Gainesville Michael D. Dukes, Associate Professor, Agricultural and Biological Engineering Department - Gainesville Mary L. Lamberts, Extension Agent IV, District V - Miami-Dade County - Homestead Andrew W. MacRae, Assistant Professor, Gulf Coast Research and Education Center - Wimauma Eugene McAvoy, Extension Agent IV, Hendry County, Labelle Joseph W. Noling, Professor, Citrus Research and Education Center - Lake Alfred Stephen M. Olson, Professor, North Florida Research and Education Center - Quincy Monica Ozores-Hampton, Assistant Professor, Southwest Florida Research and Education Center – Immokalee Natalia Peres, Associate Professor, Gulf Coast Research and Education Center - Wimauma James F. Price, Associate Professor, Gulf Coast Research and Education Center - Wimauma Richard N. Raid, Professor, Everglades Research and Education Center - Belle Glade Pam D. Roberts, Professor, Southwest Florida Research and Education Center - Immokalee Bielinski M. Santos, Assistant Professor, Gulf Coast Research and Education Center - Wimauma Eric H. Simonne, Professor, Office of District Directors - Gainesville Scott A. Smith, Coordinator, Economic Analysis, Food and Resource Economics Department - Gainesville Crystal A. Snodgrass, Extension Agent I, Manatee County - Palmetto David D. Sui, Extension Agent II, Palm Beach County - West Palm Beach Gary E. Vallad, Assistant Professsor, Gulf Coast Research and Education Center - Wimauma Susan E. Webb, Associate Professor, Entomology and Nematology Department - Gainesville Alicia J. Whidden, Extension Agent II, Hillsborough County, Seffner Vance M. Whitaker, Assistant Professor, Gulf Coast Research and Education Center – Wimauma Shouan Zhang, Assistant Professor, Tropical Research adn Education Center - Homestead Lincoln Zotarelli, Assistant Professor, Horticultural Sciences Department - Gainesville COVER PHOTOS Top left – umble bee visiting B Center right – lossom end rot and B Bottom left –Watermelon rind necrosis watermelon male flower poor pollination of Bottom right – outhern blight S Top right- Seedless watermelon fruit watermelon fruit (Sclerotium rolfsii) on Center left – Powdery mildew on cantaloupe fruit underside of cantoloupe leaf (photo credits Josh Freeman) (photo credits Mathews Paret) (photo credits Mathews Paret) ACKNOWLEDGEMENT The purpose of this book is to provide the best and most up-to-date information available to the primary users of thisbook - the Florida vegetable industry. This is possible because of the efforts of many University of Florida faculty in severallocations around the State. The editors gratefully acknowledge their contributions. The editors also wish to acknowledge thecontributions of the following faculty who have retired or are no longer involved in extension:Richard P. Cromwell George Hochmuth Thomas A. Kucharek O.N. Nesheim Bill M. StallKent E. Cushman Chad Hutchinson Kenneth D. Shuler Kenneth Pernezny Charles VavrinaCraig.K. Chandler Freddie Johnson Donald N. Maynard Allen G. Smajstrla Page ii
CONTENTSChapter 1. Introduction Chapter 14. Onion, Leek, and Chive Production in FloridaS.M. Olson........................................................................................... 1 S.M. Olson, P.J. Dittmar, N.A. Peres, S.E. Webb........................... 173Chapter 2. Soil and Fertilizer Management for Vegetable Chapter 15. Minor Vegetable Crops: Beets, Carrots, CeleryProduction in Florida and ParsleyG.D. Liu, E.H. Simonne and G.J. Hochmuth.................................... 3 M. Ozores-Hampton, P.J. Dittmar, S.E. Webb, R.N. Raid, S.M. Olson....................................................................................... 187Chapter 3. Principles and Practices of Irrigation Management forVegetables Chapter 16. Pepper Production in FloridaM.D. Dukes, L. Zotarelli, G.D. Liu and E.H. Simonne................... 17 S.M. Olson, P.J. Dittmar, G.E. Vallad, S.E. Webb, E.J. McAvoy, S.A. Smith, M. Ozores-Hampton, B.M Santos......... 223Chapter 4. Nematodes and Their ManagementJ.W. Noling........................................................................................ 29 Chapter 17. Potato Production in Florida L. Zotarelli, P.D. Roberts, P.J. Dittmar, S.E. Webb, S.A. Smith,Chapter 5. Weed Management B.M. Santos, S.M. Olson................................................................. 243P.J. Dittmar and A.W. MacRae......................................................... 39 Chapter 18. Radish Production in FloridaChapter 6. Alternative to Methyl Bromide Soil Fumigation for M. Ozores-Hampton, P.J. Dittmar, R.N. Raid, S.E. Webb,Florida Vegetable Production E.J. McAvoy..................................................................................... 261J.W. Noling, D.A. Botts and A. W. MacRae..................................... 47 Chapter 19. Spinach Production in FloridaChapter 7. Cole Crop Production in Florida S.M. Olson, P.J. Dittmar, S.E. Webb, R.N. Raid............................ 269S.M. Olson, P.J. Dittmar, G.E. Vallad, S.E. Webb, S.A. Smith........ 55 Chapter 20. Strawberry Production in FloridaChapter 8. Specialty Asian Vegetable Production in Florida B.M. Santos, N.A. Peres, J.F. Price, V.M. Whitaker, P.J. Dittmar,M.L. Lamberts, E.J. McAvoy, D.D. Sui, A.J. Whidden, S.M. Olson, S.A. Smith ................................................................... 281C.A. Snodgrass.................................................................................. 81 Chapter 21. Sweet Corn Production in FloridaChapter 9. Cucurbit Production in Florida M. Ozores-Hampton, P.J. Dittmar, S.M. Olson, S.E. Webb,S.M. Olson, P.J. Dittmar, P.D. Roberts, S.E. Webb, S.A. Smith...... 87 S.A. Smith, R.N. Raid, E.J. McAvoy............................................... 293Chapter 10. Eggplant Production in Florida Chapter 22. Sweetpotato Production in FloridaB.M. Santos, P.J. Dittmar, S. Zhang, S.E. Webb, S.M. Olson, M.L. Lamberts, P.J. Dittmar,S.A. Smith, E.J. McAvoy, M. Ozores-Hampton.............................. 111 S. Zhang, S.E. Webb........................................................................ 309Chapter 11. Legume Production in Florida: Snapbean, Lima Bean, Chapter 23. Tomato Production in FloridaSouthern pea, Snowpea S.M. Olson, P.J. Dittmar, G.E. Vallad, S.E. Webb, S.A. Smith,S.M. Olson, P.J. Dittmar, S.E. Webb, S. Zhang, E.J. McAvoy, B.M Santos, M. Ozores-Hampton............................ 321S.A. Smith, E.J. McAvoy, M. Ozores-Hampton.............................. 127 Chapter 24. Tropical Root Crop Production in FloridaChapter 12. Lettuce, Endive, Escarole Production in Florida M. L. Lamberts and S.M. Olson..................................................... 345B.M. Santos, P.J. Dittmar, R.N. Raid, S.E. Webb........................... 143Chapter 13. Okra Production in FloridaB.M. Santos, P.J. Dittmar, S.M. Olson, S.E. Webb, S. Zhang........ 163 Page iii
ADDITIONAL REFERENCESMore Information from the UF/IFAS Marketing Strategies for Vegetable Principles of micro irrigation:Electronic Database Information System Growers: http://edis.ifas.ufl.edu/WI007(EDIS, http://edis.ufas.ufl.edu): http://edis.ifas.ufl.edu/document_cv116 Treating irrigation systems with chlorine:1. on-line Chapters of previous editions of Production Costs for Selected Florida http://edis.ifas.ufl.edu/AE080the Vegetable Production Handbook Vegetables: http://edis.ifas.ufl.edu/document_cv117 Water quality/quantity best managementVariety Selection: practices for Florida vegetable and agro-http://edis.ifas.ufl.edu/document_cv102 Pesticide Provisions of the Florida nomic crops: Agricultural Worker Safety Act (FAWSA): http://www.floridaagwaterpolicy.com/PDF/Seed Quality and Seeding Technology: http://edis.ifas.ufl.edu/document_cv289 Bmps/Bmp_VeggieAgroCrops2005.pdfhttp://edis.ifas.ufl.edu/document_cv103 Principles and Practices of Food Safety for Water wells for Florida irrigation systems:Transplant Production: Vegetable Production in Florida: http://edis.ifas.ufl.edu/WI002http://edis.ifas.ufl.edu/document_cv104 http://edis.ifas.ufl.edu/document_cv288 Weather and Climate Tools for AgriculturalMulching: Introduction to Organic Crop Production: Producers:http://edis.ifas.ufl.edu/document_cv105 http://edis.ifas.ufl.edu/document_cv118 http://edis.ifas.ufl.edu/AE440Row Covers for Growth Enhancement:http://edis.ifas.ufl.edu/document_cv106 2. Additional References:Pesticide Safety: Automatic irrigation based on soil mois-http://edis.ifas.ufl.edu/document_cv108 ture for vegetable crops: http://edis.ifas.ufl.edu/AE354Interpreting PPE Statements on PesticideLabels: Causes and prevention of emitter plugginghttp://edis.ifas.ufl.edu/document_cv285 in microirrigation systems: http://edis.ifas.ufl.edu/AE032The Worker Protection Standard:http://edis.ifas.ufl.edu/document_cv138 Drip-irrigation Systems for Small Conventional Vegetable Farms andCalibration of Chemical Applicators Used Organic Vegetable Farms:in Vegetable Production: http://edis.ifas.ufl.edu/HS388http://edis.ifas.ufl.edu/document_cv110 Field devices for monitoring soil waterInsects that Affect Vegetable Crops: content:http://edis.ifas.ufl.edu/document_cv111 http://edis.ifas.ufl.edu/AE266Integrated Disease Management for Good worker health and hygiene practices:Vegetable Crops in Florida: Training manual for produce handlers:http://edis.ifas.ufl.edu/document_cv291 http://edis.ifas.ufl.edu/FY743Yields of Vegetables: http://edis.ifas.ufl. Guidelines for enrolling in Florida’s BMPedu/document_cv114 program for vegetable crops: http://edis.ifas.ufl.edu/HS367Handling, Cooling and SanitationTechniques for Maintaining Postharvest Injection of chemicals into irrigationQuality: systems: Rates, volumes and injectionhttp://edis.ifas.ufl.edu/document_cv115 periods: http://edis.ifas.ufl.edu/AE116 Page iv
CROP INDEXCrop Pages Crop Pages Crop Pages Crop PagesAsian vegetables 81-86 Tropical root crops 345-351 Lima bean 127-142 Southernpea 127-142Bean 127-142 Chive 173-185 Mustard 55-79 Spinach 269-279Beet 187-221 Collards 55-79 Okra 163-171 Squash 87-110Broccoli 55-79 Cucumber 87-110 Onion 173-185 Strawberry 281-291Cabbage 55-79 Eggplant 111-125 Parsley 187-221 Sweet corn 293-307Cantaloupe 87-110 Endive, Escarole 143-161 Pepper 223-242 Sweetpotato 309-319Carrot 187-221 Kale 55-79 Potato 243-259 Tomato 321-344Cauliflower 55-79 Leek 173-185 Radish 261-268 Turnip 55-79Celery 187-221 Lettuce 143-161 Snowpea 127-142 Watermelon 87-110 FLORIDA PESTICIDE EMERGENCY PHONE LIST Call 911 for pesticide emergencies or the appropriate contact below: * National Pesticide Information Center (NPIC), 800-858-7378, 9:30 a.m. through 6:30 p.m., 7 days a week. * The Poison Center Emergency Telephone Service, 800-222-1222 * The manufacturer of the pesticide in question. Their phone number is listed on the pesticide label. The information above was provided by the University of Florida’s Institute of Food and Agricultural Sciences Pesticide Information Office 352-392-4721. FLORIDA COUNTY COOPERATIVE EXTENSION OFFICESALACHUA COUNTY EXTENSION OFFICE BREVARD COUNTY EXTENSION OFFICE CITRUS COUNTY EXTENSION OFFICE2800 NE 39th Avenue 3695 Lake Drive 3650 West Sovereign Path, Suite 1Gainesville, Florida 32609-2658 Cocoa, Florida 32926-4219 Lecanto, FL 34461-8070PH: (352) 955-2402 PH: (321) 633-1702 PH: (352) 527-5700FAX: (352) 334-0122 FAX: (321) 633-1890 FAX: (352) 527-5749E-MAIL: Alachua@ifas.ufl.edu EMAIL: Brevard@ifas.ufl.edu EMAIL: email@example.com://alachua.ifas.ufl.edu http://brevard.ifas.ufl.edu http://citrus.ifas.ufl.eduBAKER COUNTY EXTENSION OFFICE BROWARD COUNTY EXTENSION OFFICE CLAY COUNTY EXTENSION OFFICE1025 West Macclenny Ave. 3245 College Avenue 2463 SR 16WMacclenny, Florida 32063-9640 Davie, Florida 33314-7719 P.O. Box 278PH: (904) 259-3520 PH: (954) 357-5270 Green Cove Springs, Florida 32043-0278FAX: (904) 259-9034 FAX: (954) 357-5271 PH: (904) 284-6355E-MAIL: Baker@ifas.ufl.edu EMAIL: Broward@ifas.ufl.edu FAX: (904) 529-9776http://baker.ifas.ufl.edu www.broward.org/extension EMAIL: Clay@ifas.ufl.edu http://clay.ifas.ufl.eduBAY COUNTY EXTENSION OFFICE CALHOUN COUNTY EXTENSION OFFICE2728 E. 14th Street 20816 Central Ave. East Suite1 COLLIER COUNTY EXTENSION OFFICEPanama City, Florida 32401-5022 Blountstown, Florida 32424-2292 14700 Immokalee RoadPH: (850) 784-6105 PH: (850) 674-8323 Naples, Florida 34120-1468FAX: (850) 784-6107 FAX: (850) 674-8353 PH: (239) 353-4244EMAIL: Bay@ifas.ufl.edu EMAIL: Calhoun@ifas.ufl.edu FAX: (239) 353-7127http://bay.ifas.ufl.edu http://calhoun.ifas.ufl.edu EMAIL: Collier@ifas.ufl.edu http://collier.ifas.ufl.eduBRADFORD COUNTY EXTENSION OFFFICE CHARLOTTE COUNTY EXTENSION OFFICE2266 North Temple Avenue 25550 Harbor View Road, COLUMBIA COUNTY EXTENSION OFFICEStarke, Florida 32091-1612 Suite 3 164 SW Mary Ethel Ln,PH: (904) 966-6224 Port Charlotte, Florida 33980-2503 Lake City, Florida 32025-1597FAX: (904) 964-9283 PH: (941) 764-4340 PH: (386) 752-5384EMAIL: Bradford@ifas.ufl.edu FAX: (941) 764-4343 FAX: (386) 758-2173http://bradford.ifas.ufl.edu EMAIL: Charlotte@ifas.ufl.edu EMAIL: Columbia@ifas.ufl.edu http://charlotte.ifas.ufl.edu http://columbia.ifas.ufl.edu Page v
FLORIDA COUNTY COOPERATIVE EXTENSION OFFICESDESOSTO COUNTY EXTENSION OFFICE GILCHRIST COUNTY EXTENSION OFFICE HIGHLANDS COUNTY EXTENSION OFFICE2150 Northeast Roan Street 125 East Wade Street P.O. Box 157 4509 George Blvd.Arcadia, Florida 34266-5025 Trenton, Florida 32693-0157 Sebring, Florida 33875-5837PH: (863) 993-4846 PH: (352) 463-3174 PH: (863) 402-6540FAX: (863) 993-4849 FAX: (352) 463-3197 FAX: (863) 402-6544EMAIL: Desoto@ifas.ufl.edu EMAIL: Gilchrist@ifas.ufl.edu EMAIL: Highlands@ifas.ufl.eduhttp://desoto.ifas.ufl.edu http://gilchrist.ifas.ufl.edu http://highlands.ifas.ufl.eduDIXIE COUNTY EXTENSION OFFICE GLADES COUNTY EXTENSION OFFICE HILLSBOROUGH COUNTY EXTENSION99 Northeast 121st Street P.O. Box 640 900 US 27, SW OFFICECross City, Florida 32628-0640 P.O. Box 549 5339 County Road 579PH: (352) 498-1237 Moore Haven, Florida 33471-0549 Seffner, Florida 33584-3334FAX: (352) 498-1471 PH: (863) 946-0244 PH: (813) 744-5519EMAIL: Dixie@ifas.ufl.edu FAX: (863) 946-0629 FAX: (813) 744-5776http://dixie.ifas.ufl.edu EMAIL: Glades@ifas.ufl.edu EMAIL: Hillsborough@ifas.ufl.edu http://glades.ifas.ufl.edu http://hillsborough.ifas.ufl.eduDUVAL COUNTY EXTENSION OFFICE1010 North McDuff Ave. GULF COUNTY EXTENSION OFFICE HOLMES COUNTY EXTENSION OFFICEJacksonville, Florida 32254-2083 200 N 2nd Street 1169 East Hwy 90PH: (904) 387-8850 P.O. Box 250 Bonifay, Florida 32425-6012FAX: (904) 387-8902 Wewahitchka, Florida 32465-0250 PH: (850) 547-1108EMAIL: Duval@ifas.ufl.edu PH: (850) 639-3200 FAX: (850) 547-7433http://duval.ifas.ufl.edu FAX: (850) 639-3201 EMAIL: Holmes@ifas.ufl.edu EMAIL: Gulf@ifas.ufl.edu http://holmes.ifas.ufl.eduESCAMBIA COUNTY EXTENSION OFFICE http://gulf.ifas.ufl.edu3740 Stefani Road INDIAN RIVER EXTENSION OFFICECantonment, Florida 32533-7792 HAMILTON COUNTY EXTENSION OFFICE 1028 20th Place, Suite DPH: (850) 475-5230 1143 NW US Highway 41 Jasper, Florida Vero Beach, Florida 32960-5305FAX: (850) 475-5233 32052-5856 PH: (772) 770-5030EMAIL: Escambia@ifas.ufl.edu PH: (386) 792-1276 FAX: (772) 770-5148http://escambia.ifas.ufl.edu FAX: (386)792-6446 EMAIL: Indian@ifas.ufl.edu EMAIL: Hamilton@ifas.ufl.edu http://indian.ifas.ufl.eduFLAGLER COUNTY EXTENSION OFFICE http://hamilton.ifas.ufl.edu150 Sawgrass Road JACKSON COUNTY EXTENSION OFFICEBunnell, Florida 32110-4325 HARDEE COUNTY EXTENSION OFFICE 2741 Pennsylvania Avenue, Suite 3PH: (386) 437-7464 507 Civic Center Drive Marianna, Florida 32448-4022FAX: (386) 586-2102 Wauchula, Florida 33873-9460 PH: (850) 482-9620EMAIL: Flagler@ifas.ufl.edu PH: (863) 773-2164 FAX: (850) 482-9287http://www.flaglercounty.org FAX: (863) 773-6861 EMAIL: Jackson@ifas.ufl.edu EMAIL: Hardee@ifas.ufl.edu http://jackson.ifas.ufl.eduFRANKLIN COUNTY EXTENSION OFFICE http://hardee.ifas.ufl.edu66 Fourth Street JEFFERSON COUNTY EXTENSION OFFICEApalachicola, Florida 32320-1775 HENDRY COUNTY EXTENSION OFFICE 275 North Mulberry StreetPH: (850) 653-9337 1085 Pratt Blvd Monticello, Florida 32344-1423FAX: (850) 653-9447 P.O. Box 68 PH: (850) 342-0187EMAIL: Franklin@ifas.ufl.edu LaBelle, Florida 33975-0068 FAX: (850) 997-5260http://franklin.ifas.ufl.edu PH: (863) 674-4092 EMAIL: Jefferson@ifas.ufl.edu FAX: (863) 674-4637 http://jefferson.ifas.ufl.eduGADSDEN COUNTY EXTENSION OFFICE EMAIL: Hendry@gnv.ifas.ufl.edu2140 West Jefferson Street http://hendry.ifas.ufl.edu LAFAYETTE COUNTY EXTENSION OFFICEQuincy, Florida 32351-1905 176 Southwest Community Circle, Suite DPH: (850) 875-7255 HERNANDO COUNTY EXTENSION OFFICE Mayo, Florida 32066-4000FAX: (850) 875-7257 1653 Blaise Drive PH: (386) 294-1279EMAIL: Gadsden@ifas.ufl.edu Brooksville, Florida 34601 FAX: (386) 294-2016http://gadsden.ifas.ufl.edu PH: (352) 754-4433 EMAIL: Lafayette@ifas.ufl.edu FAX: (352) 754-4489 http://lafayette.ifas.ufl.edu EMAIL: Hernando@ifas.ufl.edu http://www.co.hernando.fl.us/county_exten- sion/ Page vi
FLORIDA COUNTY COOPERATIVE EXTENSION OFFICESLAKE COUNTY EXTENSION OFFICE MARION COUNTY EXTENSION OFFICE ORANGE COUNTY EXTENSION OFFICE1951 Woodlea Road 2232 NE Jacksonville Rd. 6021 South Conway RoadTavares, Florida 32778-4407 Ocala, Florida 34470-3615 Orlando, Florida 32812-3604PH: (352) 343-4101 PH: (352) 671-8400 PH: (407) 254-9200FAX: (352) 343-2767 FAX: (352) 671-8420 FAX: (407) 850-5125EMAIL: Lake@ifas.ufl.edu EMAIL: Marion@ifas.ufl.edu EMAIL: Orange@ifas.ufl.eduhttp://lake.ifas.ufl.edu http:// marion.ifas.ufl.edu http://orange.ifas.ufl.edu/LEE COUNTY EXTENSION OFFICE MARTIN COUNTY EXTENSION OFFICE OSCEOLA COUNTY EXTENSION OFFICE3406 Palm Beach Blvd. 2614 S.E. Dixie Hwy. 1921 Kissimmee Valley LaneFort Myers, Florida 33916-3736 Stuart, Florida 34996-4007 Kissimmee, Florida 34744-6107PH: (239) 533-4327 PH: (772) 288-5654 PH: (321) 697-3000FAX: (239) 485-2305 FAX: (772) 288-4354 FAX: (321) 697-3010EMAIL: Lee@ifas.ufl.edu EMAIL: Martin@ifas.ufl.edu EMAIL: Osceola@ifas.ufl.eduhttp://lee.ifas.ufl.edu http://martin.ifas.ufl.edu http://osceola.ifas.ufl.eduLEON COUNTY EXTENSION OFFICE MIAMI-DADE COUNTY EXTENSION OFFICE PALM BEACH COUNTY EXTENSION OFFICE615 Paul Russell Road 18710 SW 288th Street 559 North Military TrailTallahassee, Florida 32301-7099 Homestead, Florida 33030-2309 West Palm Beach, Florida 33415-1311PH: (850) 606-5200 PH: (305) 248-3311 PH: (561) 233-1700FAX: (850) 606-5201 FAX: (305) 246-2932 FAX: (561) 233-1768EMAIL: firstname.lastname@example.org EMAIL: Miamiemail@example.com EMAIL: Palmbeach@ifas.ufl.eduhttp://leon.ifas.ufl.edu http://miami-dade.ifas.ufl.edu/ http://palm-beach.ifas.ufl.eduLEVY COUNTY EXTENSION OFFICE MONROE COUNTY EXTENSION OFFICE PASCO COUNTY EXTENSION OFFICE625 North Hathaway Avenue, Alt 27 1100 Simonton Street, # 2-260 36702 SR 52P.O. Box 219 Key West, Florida 33040-3110 Dade City, Florida 33525-5198Bronson, Florida 32621-0219 PH: (305) 292-4501 PH: (352) 521-4288PH: (352) 486-5131 FAX: (305) 292-4415 FAX: (352) 523-1921FAX: (352) 486-5481 EMAIL: Monroe@ifas.ufl.edu EMAIL: Pasco@ifas.ufl.eduEMAIL: http://monroe.ifas.ufl.edu http://pasco.ifas.ufl.eduLevy@ifas.ufl.eduhttp://levy.ifas.ufl.edu NASSAU COUNTY EXTENSION OFFICE PINELLAS COUNTY EXTENSION OFFICE 543350 US Hwy. 1 12520 Ulmerton RoadLIBERTY COUNTY EXTENSION OFFICE Callahan, Florida 32011-6486 Largo, Florida 33774-360210405 Northwest Theo Jacobs Way PH: (904) 879-1019 PH: (727) 582-2100Bristol, Florida 32321-3299 FAX: (904) 879-2097 FAX: (727) 582-2149PH: (850) 643-2229 EMAIL: Nassau@ifas.ufl.edu EMAIL: Pinellas@ifas.ufl.eduFAX: (850) 643-3584 http://nassau.ifas.ufl.edu http://pinellas.ifas.ufl.eduEMAIL: Liberty@ifas.ufl.eduhttp://liberty.ifas.ufl.edu OKALOOSA COUNTY EXTENSION OFFICE POLK COUNTY EXTENSION OFFICE 5479 Old Bethel Road 1702 Highway 17-98MADISON COUNTY EXTENSION OFFICE Crestview, Florida 32536-5512 South Bartow, Florida 33830184 NW College Loop PH: (850) 689-5850 P.O. Box 9005 Drawer HS03Madison, Florida 32340-1412 FAX: (850) 689-5727 Bartow, FL 33831-9005PH: (850) 973-4138 EMAIL: firstname.lastname@example.org PH: (863) 519-8677FAX: (850) 973-2000 http://okaloosa.ifas.ufl.edu FAX: (863) 534-0001EMAIL: Madison@ifas.ufl.edu EMAIL: Polk@ifas.ufl.eduhttp://madison.ifas.ufl.edu OKEECHOBEE COUNTY EXTENSION OFFICE http://polk.ifas.ufl.edu 458 Hwy. 98 North Okeechobee, FloridaMANATEE COUNTY EXTENSION OFFICE 34972-2303 PUTNAM COUNTY EXTENSION OFFICE1303 17th Street West PH: (863) 763-6469 111 Yelvington Road, Suite 1Palmetto, Florida 34221-2934 FAX: (863) 763-6745 East Palatka, Florida 32131-2114PH: (941) 722-4524 EMAIL: Okeechobee@ifas.ufl.edu PH: (386) 329-0318FAX: (941) 721-6608 http://okeechobee.ifas.ufl.edu FAX: (386) 329-1262EMAIL: Manatee@ifas.ufl.edu EMAIL: Putnam@ ifas.ufl.eduhttp://manatee.ifas.ufl.edu http://putnam.ifas.ufl.edu Page vii
FLORIDA COUNTY COOPERATIVE EXTENSION OFFICESSANTA ROSA COUNTY EXTENSION OFFICE SUMTER COUNTY EXTENSION OFFICE WAKULLA COUNTY EXTENSION OFFICE6263 Dogwood Drive 7620 State Road 471, Suite 2 84 Cedar AvenueMilton, Florida 32570-3500 Bushnell, Florida 33513-8716 Crawfordville, Florida 32327-2063PH: (850) 623-3868 PH: (352) 793-2728 PH: (850) 926-3931FAX: (850) 623-6151 FAX: (352) 793-6376 FAX: (850) 926-8789EMAIL: Santarosa@ifas.ufl.edu EMAIL: Sumter@ifas.ufl.edu EMAIL: Wakulla@ifas.ufl.eduhttp://santarosa.ifas.ufl.edu http://sumter.ifas.ufl.edu http://wakulla.ifas.ufl.eduSARASOTA COUNTY EXTENSION OFFICE SUWANNEE COUNTY EXTENSION OFFICE WALTON COUNTY EXTENSION OFFICE6700 Clark Road 1302 11th Street SW 732 North 9th StreetSarasota, Florida 34241-9328 Live Oak, Florida 32064-3600 DeFuniak Springs, FloridaPH: (941) 861-5000 PH: (386) 362-2771 32433-3804FAX: (941) 861-9886 FAX: (386) 364-1698 PH: (850) 892-8172EMAIL: Sarasota@ifas.ufl.edu EMAIL: Suwannee@ ifas.ufl.edu FAX: (850) 892-8443http://sarasota.ifas.ufl.edu http://suwannee.ifas.ufl.edu EMAIL: Walton@ ifas.ufl.edu http://walton.ifas.ufl.eduSEMINOLE COUNTY EXTENSION OFFICE TAYLOR COUNTY EXTENSION OFFICE250 W. County Home Rd. 203 Forest Park Drive WASHINGTON COUNTY EXTENSION OFFICESanford, Florida 32773-6189 Perry, Florida 32348-6340 1424 Jackson Ave., Suite APH: (407) 665-5551 PH: (850) 838-3508 Chipley, Florida 32428-1602FAX: (407) 665-5563 FAX: (850) 838-3546 PH: (850) 638-6180EMAIL: Seminole@ifas.ufl.edu EMAIL: email@example.com FAX: (850) 638-6181http://www.seminolecountyfl.gov/coopext/ http://taylor.ifas.ufl.edu EMAIL: Washington@ ifas.ufl.edu http://washington.ifas.ufl.eduST. JOHNS COUNTY EXTENSION OFFICE UNION COUNTY EXTENSION OFFICE3125 Agricultural Center Drive 25 NE 1st StreetSt. Augustine, Florida 32092-0572 Lake Butler, Florida 32054-1701PH: (904) 209-0430 PH: (386) 496-2321FAX: (904) 209-0431 FAX: (386) 496-1111EMAIL: Stjohns@ifas.ufl.edu EMAIL: Union@ifas.ufl.eduhttp://stjohns.ifas.ufl.edu http://union.ifas.ufl.eduST. LUCIE COUNTY EXTENSION OFFICE VOLUSIA COUNTY EXTENSION OFFICE8400 Picos Road, Suite 101 3100 E New York Ave.Fort Pierce, Florida 34945-3045 Deland, Florida 32724-6497PH: (772) 462-1660 PH: (386) 822-5778FAX: (772) 462-1510 FAX: (386) 822-5767EMAIL: EMAIL:Stlucie@ ifas.ufl.edu Volusia@ ifas.ufl.eduhttp://stlucie.ifas.ufl.edu http://volusia.org/extension DISCLAIMER - We appreciate the financial support of Valent in the production of this publication. The use of trade names and advertisements in thispublication is solely for the purpose of providing specific information. It is not a guarantee or warranty of the products named, and doesnot signify that they are approved to the exclusion of others of suitable composition. Use pesticides safely. Read and follow directions onthe manufacturer’s label. IFAS INFO - The Institute of Food and Agricultural Sciences is an equal opportunity/affirmative action employer authorized to provide research,educational information and other services only to individuals and institutions that function without regard to race, color, sex, age, handi-cap, or national origin. For information on obtaining other extension publications, contact your county Cooperative Extension Serviceoffice/ Florida Cooperative Service/ Institute of Food and Agricultural Sciences/ University of Florida/ Millie Ferrer-Chaney, Dean. See our web sites with electronic extension publications at http://edis.ifas.ufl.edu and for more information visit "Solutions for yourlife" at http://solutionsforyourlife.ufl.edu Page viii
Chapter 1. 2012-2013IntroductionS.M. Olson Florida ranks second among the states in fresh market More than 40 different crops are grown commerciallyvegetable production on the basis of harvested acreage in Florida with 7 of these exceeding $100 million in value.(10.3 %), production (7.9%) and value (13.8 %) of the Harvest occurs in late fall, winter and spring when at timescrops grown (Table 1.). In 2010, vegetables were harvested the only available United States supply is from Florida.from 223,500 acres and had a farm value exceeding 2.0billion dollars. On the basis of value, in 2010 tomato production accounted for about 30.2% of the state’s total value. Other A more detailed analysis of the national importance of major crops with a lesser proportion of the 2010 cropFlorida production of specific vegetables indicates that value were strawberry (17.3 %), sweet pepper (14.2 %),Florida ranks first in fresh-market value of snap bean, sweet corn (9.0 %), potatoes (6.6 %), snap beans (6.5 %),squash, sweet corn, sweet pepper, tomatoes and watermel- watermelon (5.4 %), cabbage (3.3 %), squash (2.7 %) andons. Florida ranks second in fresh market value of cabbage, cucumber (2.3 %).cucumber and strawberry.Table 1. Leading fresh market vegetable producing states, 2010. Harvested acreage Production ValueRank State Percent of total State Percent of total State Percent of total 1 California 43.2 California 49.0 California 48.2 2 Florida 10.3 Florida 7.9 Florida 13.8 3 Arizona 6.6 Arizona 7.3 Arizona 8.1 4 Georgia 6.3 Georgia 5.1 Washington 5.0 5 New York 3.9 Washington 4.0 Georgia 4.3Source: Vegetables, USDA Ag Statistics, 2011. Page 1
Chapter 2. 2012-2013Soil and Fertilizer Management for Vegetable Production in FloridaG.D. Liu, E.H. Simonne and G.J. Hochmuth BEST MANAGEMENT PRACTICES applicable technical criteria together with additional refer- With the passage of the Federal Clean Water Act ences.(FCW in 1972, states were required to assess the A)impacts of non-point sources of pollution on surface and Vegetable growers may get one-on-one informationground waters, and establish programs to minimize them. on1) the benefits for joining the BMP program, 2) howSection 303(d) of the FWCA also requires states to iden- to join it, 3) how to select the BMPs that apply to theirtify impaired water bodies and establish total maximum operation and 4) record keeping requirements by gettingdaily loads (TMDLs) for pollutants entering these water in con- tact with their county extension agent or their localbodies. Water quality parameters targeted by the TMDLs implementation team (see the vegetable BMP website atand involving vegetable production are concentrations www. imok.ufl.edu/bmp/vegetable for more information).of nitrate, phosphate, and total dissolved solids in thesewaters. A TMDL establishes the maximum amount of pol- The vegetable BMPs have adopted all current UF/IFASlutant a water body can receive and still keep its water recommendations; including those for fertilizer and irriga-quality parameters consistent with its intended use (swim- tion management (see BMP no. 33 “Optimum Fertilizerming, fishing, or potable uses). The establishment of the Management” on pg. 93 of BMP manual). Through theTMDLs is currently underway and they will be imple- implementation of a series of targeted cultural practicesmented through a combination of regulatory, non-regu- (the BMPs), growers should be able to reconcile economi-latory, and incentive-based measures. Best Management cal profitability and responsible use of water and fertilizer.Practices (BMPs) are specific cultural practices aimed at At the field level, adequate fertilizer rates should be usedreducing the load of a specific compound, while maintain- together with irrigation scheduling techniques and croping or increasing economical yields. They are tools avail- nutritional status monitoring tools (leaf analysis, petioleable to vegetable growers to achieve the TMDLs. BMPs sap testing). In the BMP manual, adequate fertilizer ratesare intended to be educational, economically sound, envi- may be achieved by combinations of UF/IFAS recom-ronmentally effective, and based on science. It is impor- mended base rates and supplemental fertilizer applications.tant to recognize that BMPs do not aim at becoming anobstacle to vegetable production. Instead, they should beviewed as a means to balance economical vegetable pro- SOILSduction with environmental responsibility. Vegetables are grown on more than 300,000 acres in The BMPs that will apply to vegetable production in various soil types throughout the state. These soil typesFlorida are described in the ‘Agronomic and V egetable include sandy soils, sandy loam soils, Histosols (organicCrop Water Quality/Water Quantity BMP Manual for muck), and calcareous marl soils. Each soil group isFlorida’. This manual was developed between 2000 and described below.2005 through a cooperative effort between state agen-cies, water management districts and commodity groups, Sandsand under the scientific leadership of the University of Sandy soils make up the dominant soil type for veg-Florida’s Institute of Food and Agricultural Sciences (UF/ etable production in Florida. Vegetables are produced onIFAS). The manual has undergone a thorough scientific sandy soils throughout the Florida peninsula and on sandyreview in 2003 and was presented to stakeholders and soils and sandy loams in the panhandle. Sandy soilsstate commodity groups for feed back in 2004. The manu- have the advantage of ease of tillage and they can produceal was adopted by reference in 2006 and by rule in Florida the earliest vegetable crops for a particular region. SandyStatutes (5M-8 Florida Administrative Code) and may be soils allow timely production operations such as plantingconsulted on-line at http://www.floridaagwaterpolicy.com/ and harvesting. Sandy soils, however, have the disadvan-PDFs/BMPs/vegetable&agronomicCrops.pdf. BMPs are tage that mobile nutrients such as nitrogen, potassium and1-to-3 page long chapters that include a picture, a working even phosphorus can be leached by heavy rain or over irri-definition of the topic, list specific things to do (BMPs) gation. Therefore, sands must be managed carefully withas well as things to avoid (pitfalls), and present existing regard to fertility programs. Sands hold very little water; Page 3
Page 4 Vegetable Production Handbook Table 1. Nutrient elements required by plants. Nutrient Deficiency symptoms Occurrence Nitrogen (N) Stems thin, erect, hard. Leaves small, yellow; on some crops On sandy soils especially after heavy rain or after (tomatoes) undersides are reddish. overirrigation. Also on organic soils during cool Lower leaves affected first. growing seasons. Phosphorus (P) Stems thin and shortened. Leaves develop purple color. On acidic soils or very basic soils. Older leaves affected first. Plants stunted and maturity delayed. Also when soils are cool and wet. Potassium (K) Older leaves develop gray or tan areas on leaf margins. On sandy soils following leaching rains or Eventually a scorch appears on the entire margin. overirrigation. Boron (B) Growing tips die and leaves are distorted. Specific diseases On soils with pH above 6.8 or on sandy, leached caused by boron deficiency include brown curd and hollow stem soils, or on crops with very high demand such as of cauliflower, cracked stem of celery, blackheart of beet, and cole crops. internal browning of turnip. Calcium (Ca) Growing-point growth restricted on shoots and roots. Specific On strongly acidic soils, or during severe droughts. deficiencies include blossom-end rot of tomato, pepper and watermelon, brownheart of escarole, celery blackheart, and cauliflower or cabbage tipburn. Copper (Cu) Yellowing of young leaves, stunting of plants. Onion bulbs are On organic soils or occasionally new mineral soils. soft with thin, pale scales. Iron (Fe) Distinct yellow or white areas between veins on youngest leaves. On soils with pH above 6.8. Magnesium (Mg) Initially older leaves show yellowing between veins, followed by On strongly acidic soils, or on leached sandy soils. yellowing of young leaves. Older leaves soon fall. Manganese (Mn) Yellow mottled areas between veins on youngest leaves, not as On soils with pH above 6.4. intense as iron deficiency. Molybdenum (Mo) Pale, distorted, narrow leaves with some interveinal yellowing of On very acidic soils. older leaves, e.g. whiptail disease of cauliflower. Rare. Zinc (Zn) Small reddish spots on cotyledon leaves of beans; light areas On wet, cold soils in early spring or where excessive (white bud) of corn leaves. phosphorus is present. Sulfur (S) General yellowing of younger leaves and growth. On very sandy soils, low in organic matter, reduced especially following continued use of sulfur-free fertilizers and especially in areas that receive little atmospheric sulfur. Chlorine (Cl) Deficiencies very rare. Usually only under laboratory conditions.therefore, irrigation management is more critical com- Muck subsidence causes problems for water and nutrientpared to other soil types used for vegetable production in management. The increase in pH due to subsidence andFlorida. Nearly all vegetable crops produced in Florida can also to the practice of flooding the Histosols to reduce oxi-be successfully grown on sandy soils. The major vegetable dation can result in increased requirements of phosphoruscrops such as tomatoes, peppers, potatoes, watermelons, and micronutrients. These nutrients can be fixed by thestrawberries, and cabbage are grown commonly on sandy high pH of the soil. Nutrient management in these situa-soils tions should involve banding rather than increased rates of nutrients. Histosols Histosols are organic soils which occur in areas through- Calcareous Rock and Marlout the peninsula, especially in southern and central The calcareous soils in southern Florida (Miami-Florida. Large organic deposits used for vegetable pro- Dade County) consist of two phases, rockland and marl.duction occur south of Lake Okeechobee. Smaller pockets Rockland soils are calcium carbonate soils consistingofof “muck” occur throughout central and northern Florida. particles that range from sand-like in size to pebble andHistosols consist largely of decomposing plant material and gravel. The rockland soils are extremely shallow, about 4are largely underlain by calcareous deposits. Muck soils to 6 inches deep. The marl is the fine- textured, clay-likehave large water and nutrient holding capacities and are phase of the calcium carbonate soils. Tomatoes, beans,used to produce crops such as the leafy vegetables (leaf summer squash, okra, sweet corn, boniato, and strawber-lettuce, and various greens), celery, sweet corn, and rad- ries can be produced in the winter months on the rocklandishes. With time, the organic matter decomposes and the soils of Miami-Dade County. Potatoes, malanga, snapmuck subsides. Thus, the pH in the muck can increase beans and sweet corn are produced onthe marl. Bothbecause of proximity to the underlying calcareous material. soils have extremely high pH, therefore, nutrients such as
Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida Page 5 Table 2. Mehlich-1 (double-acid) interpretations for vegetable crops in Florida. Very low Low Medium High Very highElement Parts per million soilP <10 10-15 16-30 31-60 >60K <20 20-35 36-60 61-125 >125Mg1 <10 10-20 21-40 41-60 >60Ca2 <100 100-200 201-300 301-400 >4001 Up to 40 lbs/a may be needed when soil test results are medium or lower2 Ca levels are typically adequate when > 300 ppm Table 3. Interpretations of Mehlich-1 soil tests for micronutrients. Soil pH (mineral soils only) 5.5 - 5.9 6.0 - 6.4 6.5 - 7.0 parts per million Test level below which there may be a crop response to applied copper. 0.1 - 0.3 0.3 - 0.5 0.5 Test level above which copper toxicity may occur. 2.0 - 3.0 3.0 - 5.0 5.0 Test level below which there may be a crop response to applied manganese. 3.0 - 5.0 5.0 - 7.0 7.0 - 9.0 Test level below which there may be a crop response to applied zinc. 0.5 0.5 - 1.0 1.0 - 3.0 When soil tests are low or known deficiencies exists, apply per acre 5 lbs Mn, 2 lbs Zn, 4 lbs Fe, 3 lb Cu and 1.5 lbs B (higher rate needed for cole crops).phosphorus and micronutrients must be banded to ensure izer. For example, a watermelon study involving K mightavailability. be conducted on a soil which tests very low in extractable K. In this situation, the soil can be expected to contrib- ute only a small amount of K for optimum watermelon growth and yield, and K must be supplied largely from SOIL TESTING fertilizer. The researcher plots the relationship between Plants require 17 elements for normal growth and crop yield and fertilizer rate. The CNR is equivalent toreproduction (Table 1). American Association of Plant the fertilizer rate above which no significant increases inFood Control officials have added nickel (Ni) to the list of yield are expected. The CNR values derived from suchessential elements in 2004. Nickel is the seventeenth ele- experiments take into account factors such as fertilizerment recognized as essential for plant growth and develop- efficiencies of the soils. These efficiencies include fertil-ment (EDIS publication on nickel essentiality is available izer leaching or fertilizer nutrient fixing capability of theonline at http://edis.ifas.ufl.edu/hs1191). The crop nutrient soil. If data are available from several experiments, thenrequirement (CNR) for a particular element is defined as reliable estimates of CNR values can be made. Using thethe total amount in lb/A of that element needed by the CNR concept when developing a fertilizer program willcrop to pro- duce economic optimum yield. This concept ensure optimum, economic yields while minimizing bothof economic optimum yields is important for vegetables pollution from overfertilization and loss of yield due tobecause a cer- tain amount of nutrients might produce underfertilization.a moderate amount of biomass, but produce negligiblemarketable product due to small fruit size. Fruit size and The CNR values are those amounts of nutrients neededquality must be consid- ered in the CNR concept for veg- to produce optimum, economic yields from a fertilizationetables. standpoint. It is important to remember that these nutrient amounts are supplied to the crop from both the soil and The CNR can be satisfied from many sources, includ- the fertilizer. The amounts are applied as fertilizers onlying soil, water, air, organic matter, or fertilizer. For when a properly calibrated soil test indicates very smallexample, the CNR of potassium (K) can be supplied from extractable amounts of these nutrients to be present in theK-containing minerals in the soil, from K retained by soil soil. Therefore, soil testing must be conducted to deterorganic matter, or from K fertilizers. mine the exact contribution from the soil to the overall CNR. Based on such tests, the amount of fertilizer that The CNR for a crop is determined from field experi- is needed to supplement the nutrition component of thements that test the yield response to levels of added fertil- native soil can be calculated (Tables 2 and 3).
Page 6 Vegetable Production Handbook Table 4. A general guideline to crop tolerance of mineral soil acidity.1Slightly tolerant (pH 6.8-6.0) Moderately tolerant (pH 6.8-5.5) Very tolerant (pH 6.8-5.0)Beet Leek Bean, snap Mustard EndiveBroccoli Lettuce Bean, lima Pea PotatoCabbage Muskmelon Brussels sprouts Pepper ShallotCauliflower Okra Carrot Pumpkin SweetpotatoCelery Onion Collard Radish WatermelonChard Spinach Corn Squash Cucumber Strawberry Eggplant Tomato Kale Turnip1 From Donald N. Maynard and George J. Hochmuth, Knott’s Handbook For Vegetable Growers, 4th edition (1997). Reprinted by permission of John Wiley & Sons, Inc. Table 5. Liming materials. Amount of Material to be used toMaterial Formula equal 1 ton of Calcium Carbonate1 Neutralizing value2(%)Calcium carbonate, calcite, hi-cal lime CaCO3 2,000 lbs 100Calcium-magnesium carbonate, dolomite CaCO3 , MgCO3 1,850 lbs 109Calcium oxide, burnt lime CaO 1,100 lbs 179Calcium hydroxide, hydrated lime Ca(OH)2 1,500 lbs 136Calcium silicate, slag CaSiO3 2,350 lbs 86Magnesium carbonate MgCO3 1,680 lbs 1191 Calcutated as (2000 x 100) / neutralizing value (%).2 The higher the neutralizing value, the greater the amount of acidity that is neutralized per unit weight of material. It is important that soil samples represent the field or nutrient-containing pesticide applications. When soil pHmanagement unit to be fertilized. A competent soil test- decreases in such soils, the solubility of micronutrientsing laboratory that uses calibrated methodologies should and probably aluminum (Al) can increase to levels thatanalyze the samples. Not all laboratories can provide may become toxic to plants.accurate fertilizer recommendations for Florida soils. TheBMP program for vegetables requires the importance of Irrigation water from wells in limestone aquifers is ancalibrated soil test. additional source of liming material usually not considered in many liming programs. The combination of routine additions of lime and use of alkaline irrigation water has resulted in soil pH greater than 8.0 for many sandy soils in LIMING south Florida. To measure the liming effect of irrigation, Current University of Florida standardized recommen- have a water sample analyzed for total bicarbonates anddations call for maintaining soil pH between 6.0 and 6.5 carbonates annually, and the results converted to pounds(Table 4). However, some vegetables, such as watermelon, of calcium carbonate per acre. Include this information inwill perform normally at lower soil pH as long as large your decisions concerning lime.amounts of micronutrients are not present in the soil. Acommon problem in Florida has been overliming, resulting It should be evident that liming (Table 5), fertilizationin high soil pH. Overliming and resulting high soil pH can (Table 6), and irrigation programs are closely related totie up micronutrients and phosphorus and restrict their each other. An adjustment in one program will often influ-availability to the crop. Overliming also can reduce the ence the other. To maximize overall production efficiency,accuracy with which a soil test can predict the fertilizer soil and water testing must be made a part of any fertilizercomponent of the CNR. management program. It is important, however, not to allow soil pH to drop Choosing ammoniacal fertilizers as nitrogen (N) sourcebelow approximately 5.5 for most vegetable production, can neutralize alkalinity in rootzone due to selective uptakeespecially where micronutrient levels in the soil may be of plants to different ions. Fertigation with ammonium-Nhigh due to a history of micronutrient fertilizer and micro- is effective for neutralization. If nitrification inhibitors are
Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida Page 7 Table 6. Effect of some fertilizer materials on soil pH. material analyses to determine specific nutrient contents. Approximate calcium Growers contemplating using organic materials as fertil-Fertilizer material carbonate equivalent (lb)1 izers should have an analysis of the material before deter-Ammonium nitrate -1200 mining the rate of application. In the case of materials such as sludges, it is important to have knowledge about theAmmonium sulfate -2200 type of sludge to be used. Certain classes of sludge are notAnhydrous ammonia -3000 appropriate for vegetable production, and in fact may notDiammonium phosphate -1250 to -1550 be permitted for land application. Decomposition rates ofPotassium chloride 0 organic materials in warm sandy soils in Florida are rapid. Therefore, there will be relatively small amounts of residu-Sodium-potassium nitrate +550 al nutrients remaining for succeeding crops. Organic mate-Nitrogen solutions -759 to -1800 rials are generally similar to mixed chemical fertilizers inNormal (ordinary) superphosphate 0 that the organic waste supplies an array of nutrients, somePotassium nitrate +520 of which may not be required on a par- ticular soil. ForPotassium sulfate 0 example, the P in poultry manure would not be required on a soil already testing high in phosphate. Usually appli-Potassium-magnesium sulfate 0 cation rates of organic wastes are determined largely byTriple (concentrated) superphosphate 0 the N content. Organic waste materials can con- tribute toUrea -1700 groundwater or surface water pollution if applied in rates1 minus sign indicates the number of pounds of calcium carbonate needed to A in excess of the crop nutrient requirement for a particular neutralize the acid formed when one ton of fertilizer is added to the soil. vegetable crop. Therefore, it is important to understand the nutrient content and the decomposition rate of the organic waste material, and the P-holding capacity of the soil. Table 7. verage nutrient concentration of selected A organic fertilizers. N P2O5 K2O N, P, K, NUTRIENT SOURCES Product % dry weight Nitrogen can be supplied in both nitrate and ammo- Blood 13 2 1 niacal forms (Table 8). Nitrate-nitrogen is generally the Fish meal 10 6 0 preferred form for plant uptake in most situations, but Bone meal 3 22 0 ammoniacal N can be absorbed directly or after conversion Cotton seed meal 6 3 1.5 to nitrate-N by soil microbes. Since this rate of conversion is reduced in cold, fumigated, or strongly acidic soils, it Peanut meal 7 1.5 1.2 is recommended that under such conditions 25% to 50% Soybean meal 7 1.2 1.5 of the N be supplied from nitrate sources. This ratio is not critical for unfumigated or warm soils. Dried commercial manure products Stockyard 1 1 2 Phosphorus (P) can be supplied from several sources, Cattle 2 3 3 including single and triple superphosphate, diammonium Chicken 1.5 1.5 2 phosphate and mono- ammonium phosphate, and mono- potassium phosphate. All sources can be effective for plant nutrition on sandy soil. However, on soils that testalso used with the fertilizers together, the neutralization very low in native micronutrient levels, diammoniumcan last much longer. Ammonium sulfate is one of the phosphate in mixtures containing micronutrients reducesmost effective fertilizers to lower rootzone pH. yields when banded in large amounts. Availability of P also can be reduced with use of diammonium phosphate compared to use of triple superphosphate. Negative effects of diammonium phosphate can be eliminated by MANURES using it for only a portion of the P requirement and by Waste organic products, including animal manures and broadcasting this material in the bed.composted organic matter, contain nutrients (Table 7) thatcan enhance plant growth. These materials decompose Potassium (K) can also be supplied from severalwhen applied to the soil, releasing nutrients that vegetable sources, including potassium chloride, potassium sulfate,crops can absorb and utilize in plant growth. The key to potassium nitrate, and potassium-magnesium sulfate. Ifproper use of organic materials as fertilizers comes in the soil-test-predicted amounts of K fertilizer are adhered to,knowledge of the nutrient content and the decomposi- there should be no concern about the K source or its rela-tion rate of the material. Many laboratories offer organic tive salt index.
Page 8 Vegetable Production HandbookTable 8. Some commonly used fertilizer sources.Nutrient Fertilizer source Nutrient content (%)Nitrogen (N) Ammonium nitrate 34 Ammonium sulfate 21 Calcium nitrate 15.5 Diammonium phosphate 18 Potassium nitrate (nitrate of potash) 13 Urea 46 Sodium-potassium nitrate (nitrate of soda-potash) 13Phosphorus (P2O5) Normal (ordinary) superphosphate 20 Triple (concentrated) superphosphate 46 Diammonium phosphate 46 Monopotassium phosphate 53Potassium (K2O) Potassium chloride (muriate of potash) 60 Potassium nitrate 44 Potassium sulfate (sulfate of potash) 50 Potassium-magnesium sulfate (sulfate of potash-magnesia) 22 Sodium-potassium nitrate 14 Monopotassium phosphate 34Calcium (Ca) Calcic limestone 32 Dolomite 22 Gypsum 23 Calcium nitrate 19 Normal superphosphate 20 Triple superphosphate 14Magnesium (Mg) Dolomite 11 Magnesium sulfate 10 Magnesium oxide 55 Potassium-magnesium sulfate 11Sulfur (S) Elemental sulfur 97 Ammonium sulfate 24 Gypsum 18 Normal superphosphate 12 Magnesium sulfate 14 Potassium-magnesium sulfate 22 Potassium sulfate 18Boron (B) Borax 11 Fertibor1 14.9 Granubor1 14.3 Solubor1 20.5Copper (Cu) Copper sulfate, monohydrate 35 Copper sulfate, pentahydrate 25 Cupric oxide 75 Cuprous oxide 89 Copper chloride 17 Chelates (CuEDTA) 13 (CuHEDTA) 6Iron (Fe) Ferrous sulfate 20 Ferric sulfate 20 Chelates (FeHEDTA) 5 to 12Manganese (Mn) Manganous sulfate 28 Manganous oxide 68 Chelates (MnEDTA) 5 to 12Molybdenum (Mo) Ammonium molybdate 54 Sodium molybdate 39Zinc (Zn) Zinc sulfate 36 Zinc oxide 80 Zinc chloride 50 Chelates (ZnEDTA) 6 to 14 (ZnHEDTA) 6 to 101Mention of a trade name does not imply a recommendation over similar materials.
Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida Page 9 Table 9. Recommendations for foliar applications of plant nutri- MICRONUTRIENTS ents. Foliar application It has been common in Florida vegetable production toNutrient Source (lb product per acre) routinely apply a micronutrient package. This practice hasBoron Borax 2 to 5 been justified on the basis that these nutrients were inex- pensive and their application appeared to be insurance for Solubor1 1 to 1.5 high yields. In addition, there were few research data andCopper Copper sulfate 2 to 5 a lack of soil-test calibrations to guide judicious applica-Iron Ferrous sulfate 2 to 3 tion of micronutrient fertilizers. Compounding the problem Chelated iron 0.75 to 1 has been the vegetable industry’s use of micronutrient-con-Manganese Manganous sulfate 2 to 4 taining pesticides for disease control. Copper (Cu), man-Molybdenum Sodium molybdate 0.25 to 0.50 ganese (Mn), and zinc (Zn) from pesticides have tended to accumulate in the soil.Zinc Zinc sulfate 2 to 4 Chelated zinc 0.75 to 1 This situation has forced some vegetable producersCalcium Calcium chloride 5 to 10 to overlime in an effort to avoid micronutrient toxicities. Calcium nitrate 5 to 10 Data have now been accumulated which permit a moreMagnesium Magnesium sulfate 10 to 15 accurate assessment of micronutrient requirements (Table1 Mention of a trade name does not imply a recommendation over similar materials. 3). Growers are encouraged to have a calibrated micro- nutrient soil test conducted and to refrain from shotgun micronutrient fertilizer applications. It is unlikely that CA, S, AND Mg micronutrient fertilizers will be needed on old vegetable land, especially where micronutrients are being applied The secondary nutrients calcium (Ca), sulfur (S), and regularly via recommended pesticides. A micronutrient soilmagnesium (Mg) have not been a common problem in test every 2 to 3 years will provide recommendations forFlorida. Calcium usually occurs in adequate supply for micronutrient levels for crop production.most vegetables when the soil is limed. If the Mehlich-1soil Ca index is above 300 ppm, it is unlikely that therewill be a response to added Ca. Maintaining correct mois- FOLIAR FERTILIZATIONture levels in the soil by irrigation will aid in Ca supplyto the roots. Calcium is not mobile in the plant; therefore, Foliar fertilization should be thought of as a last resortfoliar sprays of Ca are not likely to correct deficiencies. It for correcting a nutrient deficiency (Table 9). The plantis difficult to place enough foliar-applied Ca at the grow- leaf is structured in such a way that it naturally resistsing point of the plant on a timely basis. easy infiltration by fertilizer salts. Foliar fertilization most appropriately applies to micronutrients and not to macro- Sulfur deficiencies have seldom been documented for nutrients such as N, P and K. Foliar applications of N, P , ,Florida vegetables. Sulfur deficiency would most likely and/or K are not needed where proper soil-directed fertil-occur on deep, sandy soils low in organic matter after izer programs are in use. Leaves cannot absorb sufficientleaching rains. If S deficiency has been diagnosed, it can macronutrients (without burning the leaves) to correct anybe corrected by using S-containing fertilizers such as related deficiency. Some benefit from macronutrient foliarmagnesium sulfate, ammonium sulfate, potassium sulfate, sprays probably results when nutrients are washed by rainnormal superphosphate, or potassium-magnesium sulfate. or irrigation water off the leaf surface into the soil. TheUsing one of these materials in the fertilizer blends at lev- nutrient then may enter the plant via the roots. Amountsels sufficient to supply 30 to 40 lb S/A should prevent S of macronutrients recommended on the label of mostdeficiencies. commercial foliar products are so minuscule compared to nutrition derived from the soil that benefit to the plant Magnesium deficiency may be a problem for vegetable is highly unlikely. Additionally, fertilizer should only beproduction; however, when the Mehlich-1 soil-test index added if additional yield results and research with foliar-for Mg is below 15 ppm, 30-40 lb Mg/A will satisfy nutrient applications has not clearly documented a yieldthe Mg CNR. If lime is also needed, Mg can be added increase for vegetables.by using dolomite as the liming material. If no lime isneeded, then the Mg requirement can be satisfied through In certain situations, temporary deficiencies of Mn,use of magnesium sulfate or potassium-magnesium sulfate. Fe, Cu, or Zn can be corrected by foliar application.Blending of the Mg source with other fertilizer(s) to be Examples include vegetable production in winter monthsapplied to the soil is an excellent way of ensuring uniform when soils are cool and roots cannot extract adequateapplication of Mg to the soil. amounts of micronutrients and in cases where high pH (marl and Rockdale soils) fixes broadcast micronutrients
Page 10 Vegetable Production Handbookinto unavailable forms. Micronutrients are so termed SOLUBLE SALTSbecause small, or micro, amounts are required to satisfythe CNR. Such micro amounts may be supplied ade- Overfertilization or placement of fertilizer too close toquately through foliar applications to correct a temporary the seed or root leads to soluble salt injury or “fertilizerdeficiency. burn.” Fertilizer sources differ in their capacity to cause soluble salt injury. Therefore, where there is a history of Boron is highly immobile in the plant. To correct boron soluble salt problems, or where irrigation water is high indeficiencies, small amounts of boron must be applied fre- soluble salts, choose low-salt index fertilizer sources, andquently to the young tissue or buds. broadcast or split-apply the fertilizer. Any micronutrient should be applied only when aspecific deficiency has been clearly diagnosed. Do not STARTER FERTILIZERmake unneeded applications of micronutrients. There isa fine line between adequate and toxic amounts of these A true starter fertilizer is a soluble fertilizer, generallynutrients. Indiscriminate application of micronutrients may high in P, used for establishment of young seedlings andreduce plant growth and restrict yields because of toxic- transplants. Starter fertilizers generally work best if a smallity. Compounding the problem is the fact that the micro- amount of N and K is present along with the P. Startersnutrients can accumulate in the soil to levels which may represent a very small percentage of the overall fertilizerthreaten crop production on that soil. An important part of amount but are very important in establishing crops inany micronutrient program involves careful calculations of cool, damp soils. They can be applied with the planter at 2all micronutrients being applied, from all sources. inches to the side of the seed and 2 inches deep or can be dissolved in the transplant water and applied in the furrow. LIQUID VS. DRY FERTILIZER FERTILIZER PLACEMENT There is no difference in response of crops to similaramounts of nutrients when applied in either liquid or dry Fertilizer rate and placement must be considered togeth-form. Certain situations (use of drip irrigation or injection er. Banding low amounts of fertilizer too close to plantswheel) require clear or true solutions. However, sidedress can result in the same amount of damage as broadcastingapplications of fertilizer can be made equally well with excessive amounts of fertilizer in the bed.dry or liquid forms of nutrients. Because P movement in most soils is minimal, it should The decision to use liquid or dry fertilizer sources be placed in the root zone. Banding is generally consideredshould depend largely on economics and on the type of to provide more efficient utilization of P by plants thanapplication equipment available. The cost per unit of nutri- broadcasting. This is especially true on the high P-fixingent (e.g., dollars per unit of actual N) and the combination calcareous soils. Where only small amounts of fertilizer Pof nutrients provided should be used in any decision- are to be used, it is best to band. If broadcasting P, a smallmaking process. additional amount of starter P near the seed or transplant may improve early growth, especially in cool soils. The modified broadcast method where fertilizer is broadcast only in the bed area provides more efficient use of fertil- CONTROLLED-RELEASE FERTILIZERS izer than complete broadcasting. Several brands of controlled-release fertilizers (CRFs)are avail- able for supplying N. Some vegetables increase Micronutrients can be broadcast with the P and incorpo-in yield when controlled-release fertilizers, such as rated in the bed area. On the calcareous soils, micronutri-polymer-coated or sulfur-coated urea, or isobutylidene- ents, such as Fe, Mn, and B, should be banded or applieddiurea, are used to supply a portion of the N requirement. foliarly.Although more expensive, these materials may be usefulin reducing fertilizer losses through leaching and possible Since N and, to a lesser extent, K are mobile in sandyN loss through ammonia volatilization in high pH soils, soils, they must be managed properly to maximize cropin decreasing soluble salt dam- age, and in supplying ade- uptake. Plastic mulch helps retain these nutrients in thequate fertilizer for long-term crops such as strawberry or soil. Under non-mulched systems, split applications ofpepper. Controlled-release potassium fertilizers also have these nutrients must be used to reduce losses to leaching.been demonstrated to be beneficial for several vegetables. Here, up to one-half of the N and K may be applied to theIt is essential to match the nutrient release pattern of the soil at planting or shortly after that time. The remainingCRF with the crop’s uptake pattern. fertilizer is applied in one or two applications during the early part of the growing season. Splitting the fertilizer
Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida Page 11applications also will help reduce the potential for soluble 2. or all vegetable crops grown on any production Fsalt damage to the plants. system with one of the IFAS recommended irrigation scheduling methods, a supplemental fertilizer appli- When using plastic mulch, fertilizer placement depends cation is allowed when nutrient levels in the leaf oron the type of irrigation system (seep or drip) and on in the petiole fall below the sufficiency ranges. Forwhether drip tubing or the liquid fertilizer injection wheels bare ground production, the supplemental amountare to be used. allowed is 30 lbs/acre of N and/or 20 lbs/acre of K2O. For drip irrigated crops, the supplemental amount With seep irrigation, all P and micronutrients should be allowed is 1.5 to 2.0 lbs/A/day for N and/or K2O forincorporated in the bed. Apply 10 to 20% (but not more) of one week.the N and K with the P. The remaining N and K should beplaced in narrow bands on the bed shoulders, the number 3. upplemental fertilizer applications are allowed Sof which depends on the crop and number of rows per bed. when, for economical reasons, the harvest period hasThese bands should be placed in shallow (2- to 21/2-inch- to be longer than the typical harvest period. Whendeep) grooves. This placement requires that adequate bed the results of tissue analysis and/or petiole testing aremoisture be maintained so that capillarity is not broken. below the sufficiency ranges, a supplemental 30 lbs/Otherwise, fertilizer will not move to the root zone. acre N and/or 20 lbs/acre of K2O may be made for each additional harvest for bare ground production. Excess moisture can result in fertilizer leaching. For drip-irrigated crops, the supplemental fertilizerFertilizer and water management programs are linked. application is 1.5 to 2.0 lbs/A/day for N and/or K2OMaximum fertilizer efficiency is achieved only with close until the next harvest. A new leaf analysis and/orattention to water management. petiole analysis is required to document the need for additional fertilizer application for each additional Under either system above, fertilizing with drip irriga- harvest.tion or with a liquid fertilizer injection wheel might besuitable alternatives to the placement of all N and K in oron the bed prior to mulching. DOUBLE-CROPPING In cases where supplemental sidedressing of mulched Successive cropping of existing mulched beds is a goodcrops is needed, applications of liquid fertilizer can be practice in order to make effective use of the polyethylenemade through the mulch with a liquid fertilizer injec- mulch and fumigant. Double-cropping also can make usetion wheel. This implement is mounted on a tool bar and, of residual fertilizer in the beds. If fertilizer-N applicationsusing 30 to 40 psi pressure, injects fertilizer through a hole and amounts were properly managed for the first crop, thenpierced in the mulch. there should be negligible amounts of N- fertilizer remain- ing in the beds. The practice of adding extra fertilizer to the beds when planting the first crop, thinking that this fertilizer will aid growth of the second crop is strongly dis- SUPPLEMENTAL FERTILIZER APPLICATIONS couraged. The extra fertilizer could con- tribute to soluble- AND BMPS salt damage to the first crop, and might still be leached from the root zone before the second crop is established. In practice, supplemental fertilizer applications allowvegetable growers to numerically apply fertilizer rates A drip-irrigation system can be used to supply adequatehigher than the standard IFAS recommended rates when nutrients to each crop in a double crop system. In mostgrowing conditions require doing so. The two main grow- cases, only N and K may be needed for the second crop.ing conditions that may require supplemental fertilizer Amounts of P and micronutrients (if any) used for theapplications are leaching rains and extended harvest peri- first crop will likely remain adequate for the second cropods. Applying additional fertilizer under the following as well. Soil testing of a sample taken from the bed awaythree circumstances is part of the current IFAS fertilizer from any fertilizer bands will help determine P or micro-recommendations. Supplemental N and K fertilizer appli- nutrient needs, assuming that these nutrients were broad-cations may be made under these three circumstances: cast in the bed prior to planting the first crop. 1. or vegetable crops grown on bare ground with F If N for the first crop was not applied in excess of the seepage irrigation and without drip irrigation, a 30 CNR, then the second crop should receive an amount of lbs/ acre of N and /or 20 lbs/acre of K2O supplemen- N equal to its own CNR. Potassium requirements of the tal application are allowed after a leaching rain. A second crop can be determined as for P in cases where the leaching rain occurs when it rains at least 3 inches in K for the first crop was incorporated in the bed. Potassium 3 days, or 4 inches in 7 days. requirements for the second crop are more difficult to
Page 12 Vegetable Production Handbookdetermine in cases where K for the first crop was banded. rows within each bed. Conversions of fertilizer rates fromA moderate amount of residual K will probably remain in lb/A to lb/100 LBF, based upon these typical bed spacings,the bed from the application to the first crop. Therefore, K are shown in Table 11.requirements for the second crop will likely be slightly lessthan the CNR value for the chosen crop. Use of lb/100 LBF as a fertilizer rate assures that an appropriate rate of fertilizer will be applied, regardless of Once the crop fertilizer requirements have been ascer- the total number LBF in the cropped area. In other words,tained, the needed nutrition may be applied through the use of lb/A to express the fertilizer rate requires an adjust-drip system. Where drip irrigation is not being used, a ment based upon actual cropped area.liquid injection wheel can be used to place fertilizer in thebed for the second crop. In reality, the goal is to provide a specific concentra- tion of nutrients to plant roots; that is, a specific amount of fertilizer within a certain volume of soil. This conceptual approach makes sense because most plant roots are con- LINEAR BED FOOT (LBF) SYSTEM FOR fined within the volume of soil comprising the bed, espe- FERTILIZER APPLICATION cially under the polyethylene in the full-bed mulch system. The University of Florida Extension Soil Testing See Table 11 for the conversion of fertilizer rates in lb/ALaboratory (ESTL) employs the Standardized Fertilizer to lb/100 LBF. This table is used correctly by 1) determin-Recommendation System in which all recommendations ing the typical bed spacing from Table 10 for the crop; 2)are expressed in lb/A. These fertilizer rates are based upon locating the column containing the recommended fertilizertypical distances between bed centers for each crop (Table rate in lb/A; and 3) reading down the column until reach-10). Table 10 also indicates the typical number of planting ing the row containing the typical row spacing. This rate, in lb/100 LBF, should be used even in situations where the Table 10. ypical bed spacings for vegetables grown in Florida. T grower’s bed spacing differs from the typical bed spacing. Typical Rows of plants Vegetable Spacing1 (ft) per bed IRRIGATION MANAGEMENT Broccoli 6 2 Muskmelon 5 1 Water management and fertilizer management are linked. Changes in one program will affect the efficiency Cabbage 6 2 of the other program. Leaching potential is high for the Pepper 6 2 mobile nutrients such as N and K; therefore, over irrigation Cauliflower 6 2 can result in movement of these nutrients out of the root zone. This could result in groundwater pollution in the case Summer squash 6 2 of N. The goal of water management is to keep the irriga- Cucumber 6 2 tion water and the fertilizer in the root zone. Therefore, Strawberry 4 2 growers need knowledge of the root zone of the particular Eggplant 6 1 crop so that water and fertilizer inputs can be managed in Tomato 6 1 the root zone throughout the season. Lettuce 4 2 With increased pressure on growers to conserve water Watermelon 8 1 and to minimize the potential for nutrient pollution, it 1 pacing from the center of one bed to the center of an adjacent bed. S becomes extremely important to learn as much as pos- Table 11. Conversion of fertilizer rates in lb/A to lb/100 LBF. Recommended fertilizer rate in lb/A (N, P2O5, or K2O) Typical bed spacing (ft) 20 40 60 80 100 120 140 160 180 200 Resulting fertilizer rate in lb/100 LBF (N, P2O5, or K2O) 3 0.14 0.28 0.41 0.55 0.69 0.83 0.96 1.10 1.24 1.38 4 0.18 0.37 0.55 0.73 0.92 1.10 1.29 1.47 1.65 1.83 5 0.23 0.46 0.69 0.92 1.15 1.38 1.61 1.84 2.07 2.30 6 0.28 0.55 0.83 1.10 1.38 1.65 1.93 2.20 2.48 2.76 8 0.37 0.73 1.10 1.47 1.84 2.20 2.57 2.94 3.31 3.68
Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida Page 13sible about irrigation management. For more informa- cal precipitation can occur with these nutrients and thetion, see Chapter 3, Principles and Practices of Irrigation high calcium carbonate content of our irrigation water inManagement for Vegetables, which is part of this publica- Florida.tion. Nutrient management through irrigation tubes involves precise scheduling of N and K applications. Application rates are determined by crop growth and resulting nutri- PLANT TISSUE ANALYSIS ent demand. Demand early in the season is small and thus Analysis of plants for nutrient concentration provides a rates of application are small, usually on the order of ½good tool to monitor nutrient management programs. There to ¾ lb of N or K O per acre per day. As the crop grows,are basically two approaches to plant tissue testing: stan- nutrient demand increases rapidly so that for some vegeta-dard laboratory analyses based on dried plant parts; and the ble crops such as tomato the demand might be as high as 2plant sap testing procedures. Both procedures have value lb of N or K2O per day. Schedules of N and K applicationin nutrient management programs for vegetable crops, each have been developed for most vegetables produced withhaving its own advantages and disadvantages. drip irrigation in Florida. Schedules for these crops are pre- sented in the crop chapters in this book. Standard laboratory analyses can be very accurate andare the most quantitative procedure. However, they can betime consuming for most diagnostic situations in the field. SOIL PREPARATIONStandard laboratory analysis involves analyzing the most-recently-matured leaf of the plant for an array of nutrients. A well-prepared seed or planting bed is important forThe resulting analyses are compared against published uniform stand establishment of vegetable crops. Old cropadequate ranges for that particular crop. Laboratory results residues should be plowed down well in advance of cropthat fall outside the adequate range for that nutrient may establishment. A 6- to 8-week period between plowingindicate either a deficiency or possibly toxicity (especially down of green cover crops and crop establishment is rec-in the case of micronutrients). The most-recently- matured ommended to allow the decay of the refuse. Freshly incor-leaf serves well for routine crop monitoring and diagnostic porated plant material promotes high levels of damping-offprocedures for most nutrients. However, for the immobile organisms such as Pythium spp. and Rhizoctonia spp.nutrients such as Ca, B, and certain other micro- nutrients, Turning under plant refuse well in advance of croppingyounger leaves are generally preferred. reduces damping-off disease organisms. Land should be kept disked if necessary to keep new weed cover from Several plant sap quick test kits have been calibrated for developing prior to cropping.N and K for several vegetables in Florida. These testingkits analyze fresh plant sap for N and K. Quick test kits Chisel plowing is beneficial in penetrating and break-offer speed of analysis however, are less quantitative than ing tillage pan layers in fields. If plastic mulch culture isstandard laboratory procedures. However, quick tests are practiced, debris and large undecayed roots will createaccurate enough and if properly calibrated are a valuable problems in preparing good beds over which mulch will betool for on-the-spot monitoring of plant nutrient status with applied.the goal of making fine adjustments in fertilizer applicationprograms, especially for those involving drip irrigation. BEDDING Fields, where seepage irrigation is used or fields prone DRIP IRRIGATION/FERTIGATION to flooding, should be cropped using raised beds. Beds Drip irrigation has become a very important water man- generally range from 3 to 8 inches in height, with highagement tool for Florida vegetable growers. Approximately beds of 6 to 8 inches preferred where risk of flooding is60,000 acres of vegetables are produced with drip irriga- greatest. Raised beds dry faster than if the soil was nottion yearly in Florida. Many drip irrigation users have bedded, requiring closer attention to irrigation manage-turned to fertigation (applying nutrients through the irriga- ment especially early in the season when root systems aretion tube) to gain better fertilizer management capabil- limited. Raised beds promote early season soil warmingity. In most situations, N and K are the nutrients injected resulting in somewhat earlier crops during cool seasons.through the irrigation tube. Split applications of N and Many raised beds covered with mulch in north Florida inK through irrigation systems offers a means to capture sandy, well drained soils do not need to be as high as 6 tomanagement potential and reduce leaching losses. Other 8 inches as they do in poorly drained soils.nutrients, such as P and micronutrients, are usually appliedto the soil rather than by injection. This is because chemi-
Page 14 Vegetable Production Handbook Bedding equipment may include single or double bed- The acreage of available bahia grass pastures for rotationding discs, and curved bedding blades. After the soil is cut has been reduced and these pastures are difficult to findand thrown into a loose bed the soil is usually firmed with for many growers. As a result, growers are being forced toa bed press. In unmulched production the loosely formed more intensively crop fields. Cover crops would be help-bed may be leveled off at the top by dragging a board or ful in managing the land. When bahia grass sod is used forbar across the bed top. Boarding-off the raised beds is production, the extensive root system must be very wellcommon in unmulched watermelon production in central tilled well in advance of the cropping season to break upand northern Florida. Mulching requires a smooth, well- the clumps, especially if plastic mulch will be used. Deeppressed bed for efficient heat transfer from black mulch plowing is best to facilitate decomposition of the grassto the soil. Adequate soil moisture is essential in forming roots and stems.a good bed for mulching. Dry sandy soils will not form agood bed for a tight mulch application. Overhead irrigationis sometimes needed to supply adequate moisture to dry WINDBREAKSsoils before bedding. The use of windbreaks is an important cultural practice consideration in many vegetable crops and in most states in the United States. Windbreaks used in agriculture are COVER CROPS barriers, either constructed or vegetative, of sufficient Cover crops between vegetable cropping seasons can height to create a windless zone to their leeward or pro-provide several benefits. The use of cover crops as green tected side. Strong winds, even if a few hours in duration,manure can slightly increase soil organic matter during can cause injury to vegetable crops by: whipping plantsthe growing season. Properties of soil tilth can also be around, abrasion with solid particles (“sand blasting”), coldimproved with turning under good cover crops. The cover damage, and plant desiccation. Windbreaks are especiallycan reduce soil losses due to erosion from both wind and important to protect young plants that are most susceptiblewater. Many crops are effective at recycling nutrients left to wind damage. Abrasion to plants from wind-blown sandfrom previous crops. Recycling of nutrients is becoming is of concern in most of Florida where sandy soils arean increasingly important issue in protecting groundwater commonly used for production. Spring winds in Floridaquality. are expected each year. Many of the vegetable crops pro- duced in central and north Florida are at a young and very The selection of a cover crop is based on the seasonal susceptible stage during these windy spring periods. Stripsadaptation and intended use for the crops. Vegetable pro- of planted rye are generally recommended for temporaryduction in south Florida results in cover crops needed dur- windbreaks in those areas. Sugarcane can also serve as aing the late spring and summer months. Summer grasses more permanent windbreak in South Florida.like sorghum or sudan/sorghum hybrids have been popularamong Florida producers as a summer cover. Pearl millet The primary reasons windbreaks have been used inis another grass crop providing excellent cover but is not vegetable crops have been to reduce the physical damageas popular as sudan/sorghum. Both pearl millet and sudan/ to the crop from the whipping action of the wind and tosorghum provide a vigorous tall crop with high biomass reduce sand blasting. Young, unprotected vegetable cropsproduction and are excellent at competing with weeds. stands can be totally lost from these two actions. ManyThe cover crop selected should have resistance to nema- Florida vegetable crops are grown using plastic mulch cul-todes or at least serve as a relatively poor nematode host. ture. Young cucurbit crops, such as watermelon and can-Warm-season legumes such as sunn hemp, velvet bean taloupe grown on plastic are especially susceptible to theand hairy indigo have been noted for their resistance to whipping action of the wind. Vines of these crops eventu-nematodes. Hairy indigo has been unpopular because of its ally become anchored to the soil between mulched beds,habit of reseeding. It also has hard seed and produces vol- however, young vines can be whipped around in circlesunteers in later years. Alyceclover is another warm season for several days until they become anchored. The physicallegume with one variety, F1-3, having nematode resistance. damage by whipping and sandblasting can reduce stand,Alyceclover produces an excellent quality hay for produc- break or weaken plants, open wounds which can increaseers that can utilize hay from a cover crop. disease, and reduce flowering and fruit set. In north Florida, vegetable crops are established in the Windbreaks can also help conserve moisture for thespring and early fall. Cover crops are generally utilized crop. Effective windbreaks reduce the wind speed reach-during the winter months of November through March. ing the crops. This reduces both direct evaporations fromPopular cool season grasses have included rye, wheat, the soil and transpiration losses from the plant. Improvedoats, or ryegrass. The traditional crop rotation for water- moisture conditions can help in early season stand estab-melon growers has included the use of well-established lishment and crop growth. Air temperatures aroundbahia grass pastures followed by a crop of watermelon. the crop can also be slightly modified by windbreaks.
Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida Page 15Temperature on the leeward side of the windbreaks can be and later tilled in only the narrow strips where the plasticslightly higher than if no windbreak were present. Early mulch bed is applied. This leaves a narrow strip of ryeseason crop growth is also greater when windbreaks are between each bed and row and is generally a very effectiveutilized. Workers in several states reported increased earli- windbreak design. This design can result in more difficul-ness when rye strips were effectively used as windbreaks. ties in weed management if weeds emerge in the rye strips, however, the rye can be managed with herbicide in certain A field layout to include windbreaks must be properly crops.designed to achieve the maximum benefit. The windbreaksshould be positioned perpendicular to the prevailing winds. The most common use of rye as a windbreak is plant-This determination is perhaps more difficult in Florida than ing it into strips. Seeding rye should be done in the fallmost other states, however, windbreaks planned for protec- (October - December) for protection in a spring crop. Thetion in the spring should generally protect against winds strips are typically 5-8 ft wide and planted with a grainfrom the west or northwest. Wind protection is achieved as drill. The windbreak is a valuable component of the crop-long as the barrier is a least three feet high, the vegetation ping system and should be treated as such. A top dressingis sufficiently dense, and is positioned perpendicular to the or two of a fertilizer (at least nitrogen) will promote suffi-prevailing wind. cient early spring growth of the rye to maximize effective- ness as a windbreak. Unfertilized rye strips on low fertility The height of the windbreak is the most important fac- soil will often result in poor, thin, short strips of rye thattor in determining how far apart the strips must be located. will be less effective as a windbreak.Research on windbreaks has been conducted indicatingwind protection is afforded to a distance of 6 to 20 times The spacing of the rye strips every 30 to 40 feet alsothe height of the barrier. Field research with rye strips allows them to be used as drive roads or spray roads inshowed protection was afforded up to a distance of 10 the field. These are generally necessary in managing mosttimes the height of the barrier. For example, a healthy crop vegetable crops and therefore the rye strips are not takingof rye planted in a 5 to 8 ft wide strip using a grain drill away cropped areas of the field.and reaching a height of 3 ft would afford wind protectionup to 30 ft from the rye strip. If the same rye strip reached When the rye strips have served their purpose, they cana height of 4 ft it would afford protection up to 40 ft from be removed by mowing, rototilling, or disking. If mow-the rye strip. These examples use the calculation of protec- ing is used in a plastic mulched field, the mower shouldtion afforded up to 10 times the height of an adequate rye not throw the rye stems into the plastic area because holesstrip. will be pierced in the mulch. One insect management con- cern in using rye strips in Florida is their attractiveness to Crops such as small grains, trees, shrubs, or sugarcane thrips. Rye strips also seem to be an excellent environmentare “permeable” barriers in comparison to solid barriers for beneficial insects, especially lady beetles. If thrips needsuch as smooth constructed walls. Solid barriers are less to be managed in the rye strips, the strips could be sprayedeffective windbreaks than permeable barriers. Wind pass- just before the rye is mowed or tilled out. Once the rye ising over a solid barrier is deflected over and creates an destroyed, the thrips migrate to the crops so control wouldarea of turbulence on the protected side and returns to the be more effective while they are still on the rye strips.ground quickly. Another type of technology that can provide excellentprotection from high winds is the use of plastic row tun-nels. Polyethylene or polypropylene materials are placeover the plants in a row and held in place. Tunnels arepopular for many vegetable crops, especially cucurbitssuch as cantaloupes. The cover is removed from cucurbitswhen the first female blooms appear to allow honeybees topollinate the crops. Tunnels are generally used in conjunc-tion with rye strips because the tunnels have to be removedand once removed the crop is susceptible to wind. The most widely used windbreak in vegetable cropsacross the United States is the rye strip method. Winter orcereal rye (Secale cereale) is the preferred small grain forthis use because the seed is usually cheaper; it providesmore growth under cold temperatures and results in thehighest plant habit. In some cases the field is solid seeded
Chapter 3. 2012-2013Principles and Practices of Irrigation Management for VegetablesM.D. Dukes, L. Zotarelli, G.D. Liu and E.H. Simonne This section contains basic information on vegetable tors such as heavy metals. Among these factors, salinitywater use and irrigation management, along with some is most significant particularly in those areas close to thereferences on irrigation systems. Proper water management coast where salt content in ground water is frequently high.planning must consider all uses of water, from the source Irrigation water quality can be evaluated based on electri-of irrigation water to plant water use. Therefore, it is very cal conductivity (Table 1).important to differentiate between crop water requirementsand irrigation or production system water requirements. There are two main issues related to salinity: short term,Crop water requirements refer to the actual water needs for i.e., effect of water electrical conductivity on a particularevapotranspiration (ET) which is related to soil type and crop and long term, namely, soil salinization. There isplant growth, and primarily depend on crop development abundant biodiversity in crop tolerance to salinity stressesand climatic factors which are closely related to climatic (Tables 2 and 3). Generally speaking, vegetable crops aredemands. Irrigation requirements are primarily determined more susceptible than cereal crops.by crop water requirements, but also depend on the charac-teristics of the irrigation system, management practices andthe soil characteristics in the irrigated area. Table 1. Suggested criteria for irrigation water quality based on electrical conductivity. Concentration EC2 (TDS)1 Gravimetric BEST MANAGEMENT PRACTICES (BMP) Classes Water quality (dS/m)4 (PPM)3 FOR IRRIGATION Class 1 Excellent < 0.25 175 BMPs have historically been focused on nutrient man- Class 2 Good 0.25 - 0.75 175-525agement and fertilizer rates. However, as rainfall or irriga-tion water is the vector of off-site nutrient movement of Class 3 Permissible5 0.76 - 2.00 525-1400nitrate in solution and phosphate in sediments as well as Class 4 Doubtful6 2.01 - 3.00 1400-2100other soluble chemicals, proper irrigation management Class 5 Unsuitable6 >3.00 2100directly affects the efficacy of a BMP plan. The irrigation Source: T.A. Bauder, R.M. Waskom and J.G. Davis. 2007. Colorado State UniversityBMPs in the “Water Quality/Quantity Best Management Cooperative Extension Fact Sheet #: 0.506 Also available online at http://lubbock.Practices for Florida Vegetable and Agronomic Crops” tamu.edu/irrigate/documents/2074410-B1667.pdf(accessible at www.floridaagwaterpolicy.com) manual 1TDS = total dissolved solidscover all major aspects of irrigation such as irrigation 2EC = electrical conductivitysystem design, system maintenance, erosion control, and 3PPM = parts per millionirrigation scheduling. 4dS/m at 25° C = mmhos/cm 5Leaching needed if used. 6Good drainage needed and sensitive plants will have difficulty obtaining stands. IRRIGATION WATER QUALITY CRITERIA Understanding irrigation water quality is critical for Table 2. Threshold and zero yield salinity levels for four salinitysustainability of vegetable production. In some area of groups.Florida, water quality impacts crop productivity more Threshold Salinity Zero Yield Salinitythan soil fertility, pest and weed control, variety and otherfactors. Irrigation water quality is determined by the fol- Salinity Rating dS/mlowing: (1) salinity hazard: total soluble salt content; (2) Sensitive 1.4 8.0sodium hazard: ratio of sodium (Na+) to calcium (Ca2+) Moderately Sensitive 3.0 16.0and magnesium (Mg2+) ions; (3) water pH; (4) alkalinity: Moderately Tolerant 6.0 24.0carbonate and bicarbonate; specific ions: chloride (Cl-), Tolerant 10.0 32.0sulfate (SO42-), boron (BO3-), and nitrate-nitrogen (NO3-N);(5) organic contaminates: oil pollutants and (6) other fac- Available online at http://edis.ifas.ufl.edu/ae091 Page 17
Page 18 Vegetable Production Handbook Table 3. Salinity level (dS/m) of irrigation water for 100% Table 4. Application efficiency for water delivery systems used productivity (zero yield loss) or 0 productivity (zero yield) in in Florida vegetable production Irrigation system Application efficiency (Ea) Zero yield loss Zero yield Overhead 60-80%Species Salinity level (dS/m) Seepage1 20-70%Beans 1.0 6.5 Drip2 80-95%Beets 4.0 15.0 1 E a greater than 50% are not expected unless tailwater recovery isBroccoli 2.8 13.5 used 2 With or without plastic mulchCabbage 1.8 12.0Cantaloupe 2.2 16.0Carrot 1.0 8.0 Field PreparationCucumger 2.5 10.0 Field preparation water is used to provide moisture toLettuce 1.3 8.0 the filed soil for tillage and bed formation. The water usedOnion 1.2 7.5 for field preparation depends on specific field cultural practices, initial soil moisture conditions, the depth to thePepper 1.5 8.5 natural water table, and the type of irrigation system. Drip-Potato 1.7 10.0 irrigated fields on sandy soils often require an additionalRadish 1.2 9.0 irrigation system for field preparation because drip tubesSpinach 2.0 15.0 are not installed until the beds are formed. Many drip irri-Sweet corn 1.7 10.0 gated vegetable fields may also require an overhead or sub- irrigation system for field preparation. However, sprinklerSweet potato 1.5 10.5 irrigation systems can meet different water requirements.Tomato 2.5 12.5 For example, sprinkler irrigation systems installed in manyTurnip 0.9 12.0 strawberry production fields can work for both irrigationZucchini squash 4.7 15.0 and frost protection. These systems are also used for field preparation and may apply one or more inches of waterAfter Ayers and Wescott, 1985. Available online at http://edis.ifas.ufl.edu/ae091 for this purpose. Subirrigated fields use the same system for field preparation as well as for crop establishment, plant growth needs and frost protection. Subirrigation Also, different vegetable species differ significantly in water management requirements depend on the soil char-tolerance to salinity stress. For example, tomato is rela- acteristics within the irrigated field and surrounding areas.tively toleranct to salinity stress. At 1 dS m-1 tomato yield Sufficient water must be provided to raise the water tableincreased with N rate but no yield response to N fertiliza- level as high as 18 to 24 inches below the soil surface.tion at 5 dS m-1. However, carrot is rated as a sensitive Water is required to fill the pores of the soil and also satis-crop. Root yield declines 14% for every unit increase in fies evaporation and subsurface runoff requirements. Assalinity beyond the threshold of 1.0 dS m-1. Therefore, a rough guide, 1.0 to 2.5 inches of water are required forirrigation management for vegetable production needs to each foot of water table rise. For example, a field with abe more careful. To avoid any accidently economic loss, pre-irrigation water Table 60 inches deep may need about 2before irrigating vegetable crops, irrigation water quality inches of water to raise the water table to 18 inches, whileshould be checked based on electrical conductivity with an a pre-irrigation water table at 48 inches may require 5appropriate salinity meter at least once a year, particularly inches of water for the same result.in the near coastal areas. Vegetable growers may need toconsult their extension agent to interpret the results. Crop Establishment Vegetables that are set as transplants, rather than direct seeded require irrigation for crop establishment in excess of crop ET. Establishment irrigations are used to either USES OF IRRIGATION WATER keep plant foliage wet by overhead sprinkler irrigation (to Irrigation systems have several uses in addition to water avoid desiccation of leaves) or to maintain high soil mois-delivery for crop ET. Water is required for a preseason ture levels until the root systems increase in size and plantsoperational test of the irrigation system to check for leaks start to actively grow and develop. Establishment irriga-and to ensure proper performance of the pump and power tion practices vary among crops and irrigation systems.plant. Irrigation water is also required for field preparation, Strawberry plants set as bare-root transplants may requirecrop establishment, crop growth and development, within- 10 to 14 days of frequent intermittent overhead irrigationseason system maintenance, delivery of chemicals, frost for establishment prior to irrigation with the drip system.protection, and other uses such as dust control. The amount of water required for crop establishment can
Chapter 3: Principles and Practices of Irrigation Management for Vegetables Page 19range widely depending on crop, irrigation system, and flushing cycle should be 10 minutes longer than the travelclimate demand. Adequate soil moisture is also needed for time of the fertilizer from the irrigation point to the farthestthe uniform establishment of direct-seeded vegetable crops. point of the system. Crop Growth and Development System Maintenance Irrigation requirements necessary to meet the ET needs Irrigation systems require periodic maintenance through-of a crop depend on the type of crop and growth stage, field out the growing season. These activities may require systemsoil characteristics, irrigation system type and capacity. operation during rainy periods to ensure that the system isDifferent crops vary in growth characteristics that result in ready when needed. In addition, drip irrigation systems maydifferent relative water use rates. Soils differ in texture and require periodic maintenance to prevent clogging and sys-hydraulic characteristics such as available water-holding tem failure. Typically, cleaning agents are injected weekly,capacity (AWHC) and capillary movement. Because sands but in some instances more frequent injections are needed.generally have very low AWHC values (3% to 6% is com-mon), a 1% change in AWHC affects irrigation practices. Frost Protection For some crops, irrigation is used for frost protection Water Application (Irrigation requirement) during winter growing seasons. For strawberry production, Irrigation systems are generally rated with respect to sprinkler irrigation is primarily used with application ratesapplication efficiency (Ea), which is the fraction of the of about 0.25 inches per hour during freeze events. Waterwater that has been applied by the irrigation system and freezes at 32ºF, while most plant tissues freeze at lowerthat is available to the plant for use (Table 4). Applied temperatures. Overhead freeze protection is efficient forwater that is not available to the plant may have been air temperature as low as 26-28ºF, but seldom below. Forlost from the crop root zone through evaporation or wind vegetable fields with subirrigation systems, the relativelydrifts of spray droplets, leaks in the pipe system, surface higher temperature of groundwater can be used for coldrunoff, subsurface runoff, or deep percolation within the protection. Growers may also irrigate to raise the waterirrigated area. Irrigation requirements (IR) are determined table throughout the field. Frost protection water require-by dividing the desired amount of water to provide to the ments vary and depend on the severity and duration ofplant (ETc), by the Ea as a decimal fraction (Eq.). For freeze events, the depth to the existing water table level,example, if it is desired to apply 0.5 inches to the crop with and field hydraulic characteristics. For more information,a 75% efficient system, then 0.5/0.75 = 0.67 inches would consult IFAS bulletin HS931 “Microsprinkler irrigation forneed to be pumped. Hence, when seasonal water needs are cold protection of Florida citrus” (http:// http://edis.ifas.assessed, the amount of water needed should be based on ufl.edu/ch182) and bulletin SL296 “Citrus Cold Weatherthe irrigation requirement and all the needs for water, and Protection and Irrigation Scheduling Tools Using Floridanot only on the crop water requirement. For more informa- Automated Weather Network (FAWN) Data” (http://edis.tion, consult IFAS bulletin 247 “Efficiencies of Florida ifas.ufl.edu/ss509).agricultural irrigation systems” (http://edis.ifas.ufl.edu/AE110) and bulletin 265 “Field evaluation of microirriga- Other Usestion water application uniformity” (http://edis.ifas.ufl.edu/ Other irrigation uses vary according to the type of crop,AE094). Catch cans can be used in the field to measure the system characteristics, and field location. Some examplesactual amount of water applied. include: periodic overhead irrigation for dust control; wet- ting of dry row middles to settle dust and prevent sand fromEq.  Irrigation requirement = blowing during windy conditions; and, wetting of roadways Crop water requirement / Application efficiency and drive aisles to provide traction of farm vehicles. IR = ETc/Ea IRRIGATION SCHEDULING Fertigation/Chemigation Irrigation systems are often used for delivery of chemi- Irrigation scheduling consists simply of applying watercals such as fertilizers, soil fumigants, or insecticides. The to crops at the “right” time and in the “right” amount andcrop may require nutrients when irrigation is not required, it is considered an important BMP. The characteristicse.g. after heavy rainfall. Fertilizer injection schedules of the irrigation system, crop needs, soil properties, andbased on soil tests results are provided in each crop pro- atmospheric conditions must all be considered to properlyduction chapter of this production guide. Fertigation should schedule irrigations. Poor timing or insufficient waternot begin until the system is pressurized. It is recom- application can result in crop stress and reduced yieldsmended to always end a fertigation/ chemigation event from inappropriate amounts of available water and/orwith a short flushing cycle with clear water to avoid the nutrients. Excessive water applications may reduce yieldaccumulation of fertilizer or chemical deposits in the irri- and quality, are a waste of water, and increase the risk ofgation system, and/or rinse crop foliage. The length of the nutrient leaching.
Page 20 Vegetable Production Handbook A wide range of irrigation scheduling methods is used for splitting irrigation, (4) a method to account for rainfall,in Florida, with corresponding levels of water management and (5) record keeping (Table 6). For seepage irrigation,(Table 5). The recommended method (level 5) for schedul- the water table should be maintained near the 18-inching irrigation (drip or overhead) for vegetable crops is to depth (measured from the top of the bed) at planting anduse together: the crop water requirement method that takes near the 24-inch depth when plants are fully grown. Waterinto account plant stage of growth associated with mea- tables should be maintained at the proper level to ensuresurements of soil water status, and guidelines for splitting optimum moisture in the bed without leading to oversatu-irrigation (see below). A typical irrigation schedule con- ration of the root zone and potential losses of nutrients.tains (1) a target crop water requirement adjusted to crop Water tables can be monitored with a section of PVC pipestage of growth and actual weather demand, (2) adjustment sunk in the soil with a calibrated float inside the PVC pipe.of irrigation application based on soil moisture, (3) a rule The calibrated float can be used to determine the exact level of the water table. Table 5. Levels of water management and corresponding irriga- tion scheduling method Soil Water Status, Soil Water Tension and Soil Volumetric Water ContentWater Generally, two types of sensors may be used for mea-Mgt. Level Irrigation scheduling method surements of soil water status, those that measure soil0 Guessing (irrigate whenever), not recommended water potential (also called tension or suction) and those1 Using the ”feel and see” method, see ftp://ftp-fc. that measure volumetric water content directly. Soil water sc.egov.usda.gov/MT/www/technical/soilmoist.pdf tension (SWT) represents the magnitude of the suction2 Using systematic irrigation (Example: ¾ in. every 4th (negative pressure) the plant roots have to create to free day; or 2hrs every day) soil water from the attraction of the soil, and move it3 Using a soil water tension measuring tool or soil mois- into the root cells. The dryer the soil, the higher the suc- ture sensor to start irrigation tion needed, hence, the higher SWT. SWT is commonly4 Schedule irrigation and apply amounts based on a bud- expressed in centibars (cb) or kilopascals (kPa; 1cb = geting procedure and checking actual soil water status 1 kPa; 7 kPa = 1psi). For most vegetable crops grown on51 Adjusting irrigation to plant water use (ETo), and using the sandy soils of Florida, SWT in the rooting zone should a dynamic water balance based on a budgeting pro- be maintained between 6 (slightly above field capacity) cedure and plant stage of growth, together with using and 15 cb. Because of the low AWHC of Florida soils, a soil water tension measuring tool or soil moisture sensor most full-grown vegetable crops will need to be irrigated1 Recommended method daily. During early growth, irrigation may be needed only two to three times weekly. SWT can be measured in the Table 6. Summary of irrigation scheduling guidelines for vegetable crops grown in Florida. Irrigation system1Irrigationscheduling component Seepage2 Drip31- Target water application rate Keep water table between 18 and 24 Historical weather data or crop evapotranspiration (ETc) calculated inch depth from reference ET or Class A pan evaporation2- Fine tune application with soil Monitor water table depth with Maintain soil moisture level in the root zone between 8 and 15 cbarmoisture measurement observation wells (or 8% and 12% available soil moisture3- Determine the contribution of Typically, 1 inch rainfall raises the Poor lateral water movement on sandy and rocky soils limits therainfall water table by 1 foot contribution of rainfall to crop water needs to (1) foliar absorption and cooling of foliage and (2) water funneled by the canopy through the plan hole.4- Rule for splitting irrigation Not applicable. However, a water Irrigations greater than 12 and 50 gal/100 ft (or 30 min and 2 hrs for budget can be developed drip tapes with medium flow-rate) when plants are small and fully grown, respectively are likely to push the water front being below the root zone5-Record keeping Irrigation amount applied and total Irrigation amount applied and total rainfall received4 rainfall received4 Daily irrigation schedule Days of system operation1 Efficient irrigation scheduling also requires a properly designed and maintained irrigation system2 Practical only when a spodic layer is present in the field3 On deep sandy soils4 Required by the BMPs
Chapter 3: Principles and Practices of Irrigation Management for Vegetables Page 21field with moisture sensors or tensiometers. For more in for overhead or seepage irrigation, or 34 gal/100ft forinformation on SWT measuring devices, consult IFAS cir- drip irrigation with 6 ft bed centers in plasticulture) in acular 487 ‘Tensiometers for soil moisture measurement and single irrigation event. Right after the irrigation events,irrigation scheduling’ available at http://edis.ifas.ufl.edu/ there was a noticeable increase in soil moisture content.AE146 and bulleting 319 “Tensiometer service, testing and The degree to which the VWC increases, however, iscalibration” available at http://edis.ifas.ufl.edu/AE086. dependent upon volume of irrigation, which is normally set by the duration of irrigation event. For plastic mulched Within the category of volumetric sensors, capacitance drip irrigation in sandy soils, long irrigation events resultbased sensors have become common in recent years due to in a relatively large increase in soil moisture in the areaa decrease in cost of electronic components and increased below the drip emitter. The spike in soil moisture appearsreliability of these types of sensors. However, sensors to only be temporary, as the irrigation water rapidly drainsavailable on the market have substantially different accura- down beyond the 6-inch zone (observed by the decreasecies, response to salts, and cost. Soil moisture sensors are in VWC). This rapid spike in soil water content indicatesdetailed in the publication, “Field Devices for Monitoring that the VWC rapidly reaches a point above the soil waterSoil Water Content” (http://edis.ifas.ufl.edu/AE266). All holding capacity and the water percolated down to deepermethods under this definition estimate the volume of water soil layers. Between end of day 1 and day 3 (Fig. 2), thein a sample volume of undisturbed soil [ft3/ft3 or percent- VWC declined at a constant rate due to some soil waterage]. This quantity is useful for determining how saturated extraction by drainage, but most extraction due to evapo-the soil is (or, what fraction of total soil volume is filled transpiration during the day. For sandy soils, the change inwith the soil aqueous solution). When it is expressed in the slope of drainage and extraction lines, in other words,terms of depth (volume of water in soil down to a given changing from “rapid” to “slower” decrease in soil waterdepth over a unit surface area (inches of water)), it can be content can be assumed as the “field capacity point”. Atcompared with other hydrologic variables like precipita- this time, the water has moved out from the large soiltion, evaporation, transpiration and deep drainage. pores (macropores), and its place has been taken by air. The remaining pore spaces (micropores) are still filled with Practical Determination of Soil Field Capacity Using water and will supply the plants with needed moisture. Volumetric Soil Moisture Sensors It is very important that the irrigation manager under- Examples of Irrigation Scheduling Using Volumetric Soilstands the concept of “field capacity” to establish an irri- Moisture Sensor Devicesgation control strategy goals of providing optimum soil In this section, two examples of irrigation managementmoisture for plant growth, productivity, and reduction of of vegetable crops in sandy soils using soil moisture sensorfertilizer nutrient leaching. Figure 2 represents volumetric readings stored in a data logger are provided: one examplesoil water content (VWC) at depth of 0-6 inches measured with excessive (“over”) irrigation (Fig. 3) and one withby a capacitance sensor during a period of 4 days. For adequate irrigation (Fig.4) using plasticulture. In Figure 3,the soil field capacity point determination, it is necessaryto apply an irrigation depth that resulted in saturation ofthe soil layer, in this particular case 0-6 inches. The depthof irrigation applied was 4,645 gal/ac (equivalent to 0.17 Figure 2. xample of excessive (“over”) irrigation” of the upper soil layer E (0 to 6 inch depth) moisture content for drip irrigation under plastic mulched condition for sandy soils. Black line indicates volumetric soil water content using soil moisture sensors. GreyFigure 1. xample of practical determination of soil field capacity at E line indicates Irrigation event, single daily irrigation event with 0-6 inches soil depth after irrigation event using soil moisture volume application of 65 gal/100 ft (0.18 in). Dotted line indicates sensors. soil field capacity line. Arrows indicate rainfall events.
Page 22 Vegetable Production Handbookthe irrigation events consisted of the application of a single of the length of the irrigation is necessary, to avoid overdaily irrigation event of 4,718 gal/ac (equivalent to 0.18 in irrigation (additional information about irrigation depthsfor overhead or seepage irrigation, or 36 gal/100ft for drip can be obtained in the IFAS bulletin AE72 “Microirrigationirrigation with 6-ft bed centers in plasticulture. After each in Mulched Bed Production Systems: Irrigation Depths” atirrigation event, there was an increase in the soil water (http://edis.ifas.ufl.edu/AE049).content followed by rapid drainage. Large rainfall eventsmay lead to substantial increases in soil moisture content. The example in Figure 4 received irrigation depth ofOn day 2, right after the irrigation, a large rainfall of 0.44 943 gal/ac (equivalent to 0.03 in for overhead or seep-inches occurred, which resulted in a second spike of soil age irrigation, or 6 gal/100 ft for drip irrigation with 6-ftwater content in the same day. The following irrigation bed centers in plasticulture, this irrigation depth was suf-(day 3) started when the volumetric soil water content ficient to increase the volumetric water content to a givenwas above the soil field capacity. In this case, the irriga- moisture without exceeding the “safe irrigation zone”. Ontion event of the day 3 could have been safely skipped. average, the volumetric soil water content is maintainedBetween day 3 and 6, no irrigation was applied to the crop. close to the field capacity, keeping water and nutrientsThe volumetric water content decreased from 0.14 to 0.08 in the root zone. For this particular example, there wasin3/in3. Due to the very low water holding capacity of the no deep water percolation. In addition, with the informa-sandy soils, skipping irrigation for several days could lead tion of the soil water status, the irrigation manager mightto unneeded crop water stress especially during very hot decide to not irrigate if the soil moisture content is at adays or very windy days (when high evapotranspiration satisfactory level. For example, in day 8, due to a rainfallrates may occur), or during flowering stage. Between day 6 event of 0.04 in, there was no need of irrigation becauseand 10, large daily irrigation events were repeated, exceed- the soil moisture was above the field capacity and theing the “safe irrigation zone”, and leading to more water arbitrary threshold, therefore the irrigation event of day 8drainage and nutrient leaching. was skipped. On the other hand, this “precise” irrigation management requires very close attention by the irriga- Conversely, Figure 4 shows “adequate” irrigation appli- tion manager. For a given reason (such as pump issue), thecations for a 10 day period. In this case, the irrigation irrigation was ceased in day 5 and it was resumed late inevent will start exclusively when the volumetric soil water day 6. As a result, soil water storage decreased to a certaincontent reaches an arbitrary threshold. For this particular level, and if the water shortage is prolonged, the plantssituation, the soil field capacity is known, the irrigation would be water stressed.events started when the volumetric soil moisture contentreached values below the soil field capacity (or 0.09 in3/ Tips on Installation and Placing of Soil Moisture Sensorin3). However, to maintain the soil volumetric water con- Devices in Vegetable Fieldstent in the “safe irrigation zone”, a previous determination The use of soil moisture monitoring devices (volumetric or soil water tension) has potential of save irrigation water application in a given vegetable area by reducing the num- ber of unnecessary irrigation events. However, the effec- tiveness of the use of these sensors depends of a proper installation in representative locations within vegetable fields. These sensors may be used to monitor water table levels in seepage irrigation. Sensors should be buried in the root zone of the plants to be irrigated. Most of the vegetable crops have 80% to 90% of the root zone in the upper 12 inches, which gener- ally is the soil layer with higher water depletion by evapo- transpiration. For vegetable crops cultivated in rows and irrigated by drip tapes, the sensors should be installed 2-3 inches away from the plant row. For single row crops (such as tomato, eggplant, or watermelon), the sensor should be placed in the opposite side of the drip tape, for double rowFigure 3. xample of adequate irrigation management using soil moisture E crops (pepper, squash), the sensors should be placed in sensors for monitoring the volumetric soil moisture content the between the drip tape and plant rows. upper soil layer (0 to 6 inch depth), on drip irrigation under plas- tic mulched condition for sandy soils. Black line indicates volu- Sensors need to be in good contact with the soil after metric soil water content using soil moisture sensors. Grey line burial; there should be no air gaps surrounding the sensor. indicates Irrigation event, single daily irrigation event with volume application of 943 gal/ac (0.03 in). Dotted line indicates soil field Soil should be packed firmly but not excessively around capacity line. Arrows indicate rainfall events. the sensor. In plasticulture, after the installation, the area
Chapter 3: Principles and Practices of Irrigation Management for Vegetables Page 23above the sensor should be recovered back with plastic and While these values are provided as guidelines forsealed with tape. management purposes, actual values may vary above and below these values, requiring individual site adjustments. Crop water requirement (ET) Actual daily values may be as much as 25% higher on days Crop water requirements depend on crop type, stage that are hotter and drier than normal or as much as 25%of growth, and evaporative demand. Evaporative demand lower on days that are cooler or more overcast than nor-is termed evapotranspiration (ET) and may be estimated mal. Real time ETo estimates can be found at the Floridausing historical or current weather data. Generally, refer- Automated Weather Network (FAWN) internet site (http://ence evapotranspiration (ETo) is determined for use as fawn.ifas.ufl.edu). For precise management, SWT or soila base level. By definition, ETo represents the water use moisture should be monitored daily in the field.from a uniform green cover surface, actively growing, andwell watered (such as turf or grass covered area). Crop water use (ETc) is related to ETo by a crop coef- ficient (Kc) which is the ratio of ETc to the reference Historical daily averages of Penman-method ETo values value ETo (Eq. ). Because different methods exist forare available for six Florida regions expressed in units of estimating ETo, it is very important to use Kc coefficientsacre-inches and gallons per acre (Table 7). which were derived using the same ETo estimation method as will be used to determine the crop water requirements. Table 7. Historical Penman method reference evapotranspiration (ETo) for six Florida regions expressed in (A) inches per day and (B) gallons per acre per day1.Month Northwest Northeast Central Central West Southwest SoutheastInches per day (A)JAN 0.06 0.07 0.07 0.07 0.08 0.08FEB 0.07 0.08 0.10 0.10 0.11 0.11MAR 0.10 0.10 0.12 0.13 0.13 0.13APR 0.13 0.14 0.16 0.16 0.17 0.17MAY 0.16 0.16 0.18 0.18 0.18 0.18JUN 0.17 0.16 0.18 0.18 0.18 0.17JUL 0.17 0.16 0.17 0.17 0.18 0.18AUG 0.15 0.15 0.17 0.16 0.17 0.16SEP 0.13 0.13 0.14 0.14 0.15 0.14OCT 0.09 0.10 0.11 0.11 0.12 0.12NOV 0.07 0.07 0.08 0.08 0.09 0.09DEC 0.05 0.06 0.06 0.07 0.07 0.07Gallons per acre per day2 (B)JAN 1629 1901 1901 1901 2172 2172FEB 1901 2172 2715 2715 2987 2987MAR 2715 2715 3258 3530 3530 3530APR 3530 3801 4344 4344 4616 4616MAY 4344 4344 4887 4887 4887 4887JUN 4616 4344 4887 4887 4887 4616JUL 4616 4344 4616 4616 4887 4887AUG 4073 4073 4616 4344 4616 4344SEP 3530 3530 3801 3801 4073 3801OCT 2444 2715 2987 2987 3258 3258NOV 1901 1901 2172 2172 2444 2444DEC 1358 1629 1629 1629 1901 19011 ssuming water application over the entire area, i.e., sprinkler or seepage irrigation with 100% efficiency, See Table 4 for conversion for taking into account irrigation system A efficiency.2 alculation: for overhead or seepage irrigation, (B) = (A) x 27,150. To convert values for drip irrigation (C) use (C) = (B) x bed spacing / 435.6. For example for 6-ft bed spacing C and single drip line, C in Southwest Florida in January is C = 2,172 x 6/ 435.6 = 30 gal/100 ft/day.
Page 24 Vegetable Production HandbookAlso, Kc values for the appropriate stage of growth (Tables season as compared to no-mulched system, overall water use8 and 9; Fig. 3) and production system (Tables 6 and 7) values decrease by an average of 10-30% due the reductionmust be used. in soil evaporation. ETo may be estimated from atmometers (also called modified Bellani plates) by using an adjustment With drip irrigation where the wetted area is limited and factor. During days without rainfall, ETo may be estimatedplastic mulch is often used, Kc values are lower to reflect from evaporation from an ET gauge (Ea) as ETo = Ea/0.89.changes in row spacing and mulch use. Plastic mulches sub- On rainy days (>0.2 in) ETo = Ea/0.84.stantially reduce evaporation of water from the soil surface.Associated with the reduction of evaporation is a general Eq.  Crop water requirement =increase in transpiration. Even though the transpiration rates Crop coefficient x Reference evapotranspirationunder mulch may increase by an average of 10-30% over the ETc = Kc x EToTable 8. Description of stages of growth (plant appearance and estimated number of weeks) for most vegetable crops grown in the Springin Florida1. Expected growingCrop Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 season (weeks)Bean Small plants Growing plants Pod enlargement Pod maturation 9-10 2-3 3-4 2-3 2-3Cabbage, Small plants Growing plants Head development 10-12Cauliflower, 2-3 5-6 3-4Chinese cabbageCantaloupe 6-in vine 12-in vine First flower Main fruit production Late fruit production 11-12(muskmelon) 1-2 3-4 3-4 2-3 2-3Carrot Small plants Growing plants Root development Final growth 10-13 1-2 3-4 5-7 1-2Cucumber 6-in vine 12-in vine Fruit production Late season 10-12 1-2 2-3 6-7 1-2Eggplant Small plants Growing plants Fruit production Late season 12-13 2-3 2-3 6-7 2-3Potato Small plants Large plants First flower (tube Maturation (top dies) 12-14 (after hilling) (vegetative growth) initiation and bulking) 2-4 2-4 4-6 3-5Okra Small plants Growing plants Pod production Late season 12-13 2-3 2-3 7-8 1-2Onion Small plants Growing plants Bulb development Maturation (top falls) 13-16 2-4 4-5 6-8 1-2Pepper Small plants Growing plants Pod production Last bloom Last harvest 13-15 2-3 2-3 7-8 1-2 1Pumpkin Small plants First flower Fruit enlargement Harvest 9-11(bush) 2-3 2-3 5-6 1-2Pumpkin 6-in vines 12-in vines Small fruit Large fruit Harvest 1-2 13-15(vining) 2-3 2-3 3-4 2-3Radish Small plants Rapid growth 3-5 1-2 2-4Strawberry Young plants Growing plants Early harvest Main harvest period Late harvest 23-30 October November December-January February-March AprilSummer Squash Small plants Growing plants Fruit production Late fruit production 7-9(crookneck, straight- 1-2 2-3 3-4 1neck, zucchini)Sweet corn Small plants Large plants Ear development 10-15 3-4 5-8 2-3Sweetpotato Early vine growth Expanding vines Storage root enlargement Late season 13-17 2-3 5-6 6-10Tomato Small plants 1st bloom 2nd-3rd bloom Harvest Late harvest 12-14 2-3 2-3 6-7 1-2 1-2Watermelon 6-in vines 12-in vines Small fruit Large fruit Harvest 1-2 13-15 2-3 2-3 3-4 2-31 Same growth stages used for irrigation and fertilizer schedules; for South Florida, each stage may be 30% longer because of winter planting during short days.
Chapter 3: Principles and Practices of Irrigation Management for Vegetables Page 25 Table 9. Crop coefficient estimates for use with the ETo values in Table 6 and growth stages in Table 7 for unmulched crops. (Actual values will vary with time of planting, soil conditions, cultural conditions, length of growing season and other site-specific factors)Crop Growth Stage Crop Coefficient1 Crop Growth Stage Crop Coefficient1All field-grown vegetables 1 0.202 to 0.403 Onion (dry) 3 0.95 2 Stage 14 value to 4 0.75 Stage 3 value (See Figure 3-3)Legumes: sandbean, 3 0.955 Onion (green) 3 and 4 0.95lima bean and southernpea 4 0.855Beet 3 1.00 Parsley 3 1.005 4 0.90Cole crops: Potato 3 1.10Broccoli, brussels sprouts 3 0.95 4 0.70cabbage, cauliflower 4 0.805Collards, kale, mustard, 3 0.905turnip 4 1.005Carrot 3 1.00 Radish 3 0.80 4 0.70 4 0.75Celery 3 1.00 Spinach 3 0.95 4 0.90 4 0.90Cucurbits: cucumber, 3 0.90 Sweet corn 3 1.10cantaloupe, pumpkin, 4 0.70 4 1.00squash, watermelonLettuce: endive, 3 0.95 Sweetpotato 3 1.105escarole 4 0.90 4 0.705Okra 3 1.005 4 0.9051 dapted from Doorenbos, J., and Pruitt, W. O. 1977. Crop water requirements. Irrigation and Drainage Paper No. 24, (rev.) FAO, Rome and Allen, R.G., L.S.Pereira, D. Raes, and A M. Smith. 1998. Crop evapotranspiration: Guidelines for computing crop water requirements Food and Agriculture Organization of the United Nations, Rome.2 Low plant population; wide row spacing3 High plant population; close row spacing4 0.30 or Kc value from Stage 15 Values estimated from similar crops Table 10. Crop coefficient estimates (Kc) for use with ETo values in Table 6 and growth stages in Table 7 for selected crops grown in a plasticulture system.1Crop Growth Stage Crop Coefficient (Kc) Crop Growth Stage Crop Coefficient (Kc)Cantaloupe1 1 0.35 Strawberry 1 0.4 2 0.6 (4-ft bed centers)2 2 0.5 3 0.85 3 0.6 4 0.85 4 0.8 5 0.85 5 0.8Cucumber1 1 0.25 Tomato 1 0.4 2 0.5 (6-ft bed centers) 3 2 0.75 3 0.9 3 1.0 4 0.75 4 1.0 5 0.85Summer squash1 1 0.3 Watermelon 1 0.3 2 0.55 (8-ft bed center)1 2 0.5 3 0.9 3 0.7 4 0.8 4 0.9 5 0.81 dapted from Tables 12 and 25 in Allen, R.G., L.S.Pereira, D. Raes, and M. Smith. 1998. Crop evapotranspiration: guidelines for computing crop water requirements Food and A Agriculture Organization of the United Nations, Rome.2 Adapted from Clark et al. 1993. Water Requirements and Crop Coeffcients for Tomato Production in Southwest Florida. Southwest Florida Water Management District, Brandon, FL.3 Adapted from Clark et al. 1996. Water requirements and crop coefficients of drip-irrigated strawberry plants. Transactions of the ASAE 39:905-913.
Page 26 Vegetable Production HandbookSOIL WATER HOLDING CAPACITY AND THE NEED of growth occurred in May, the corresponding ETo value is TO SPLIT IRRIGATIONS 4,914 gal/ac/day (Table 7). Daily crop water use would be estimated as: Appropriate irrigation scheduling and matching irrigationamounts with the water holding capacity of the effective root ETcrop (0.85) x (4,914 gal/ac/day) =zone may help minimize the incidence of excess leaching = 4,177 gal/ac/dayassociated with over-irrigation. In Florida sandy soils, theamount of water that can be stored in the root zone and be If the drip irrigation system can apply water to the rootavailable to the plants is limited. Usually, it is assumed that zone of the crop with an application efficiency of 85%, theapproximately 0.75 inches of water can be stored in every irrigation requirement would befoot of the root zone. Only half of that should be used beforenext irrigation to avoid plant stress and yield reduction (this Irrigation Requirement (4,177 gal/ac/day) / (0.80) =will help maintain SWT below 15 cb). Any additional water = 5,221 gal/ac/daywill be lost by deep percolation below the root zone. If the maximum water application in one irrigation event Table 11 gives approximate amount of water that can for this type of soil is 1,700 gal/ac/irrigation, then the irriga-be applied at each event in Florida sandy soil under dif- tion will have to be split:ferent production systems. When the calculated volume ofwater to be applied in one day exceeds the values in Table Number of events = 5,221 gal/acre/day) / (10, then it is necessary to split applications. The number of (1,700 gal/acre/day/irrigation event) =split irrigations can be determined by dividing the irriga- 3.1, rounded up to 4 irrigation eventstion requirement (Eq. ) by the numbers in Table 11, and each of 5,221 / 4 = 1,305 gal/acrerounding up the result to the nearest whole number. Splittingirrigation reduces both risks of water loss through deep per- Therefore, in this example, four irrigations of 1,305 gal/colation and nutrient leaching. Sandy soil with the available ac each will be needed to replace ETc, not exceed the soilwater holding capacity of 0.75 in/ft was assumed in these water holding capacity. This amount of water would be acalculations. If a soil contains more clay or organic matter good estimate for scheduling purposes under average growththe amount of water applied during one irrigation event and and average May climatic conditions. However, field mois-stored in the root zone can be increased. It is recommended ture plant status should be also monitored to determine ifto check the depth of wetting after irrigation to assure that irrigation levels need to be increased or reduced. Whilethe water is not lost from the roots by digging out a per- deficit irrigation will reduce fruit size and plant growth,pendicular profile to the drip line and observing the wetted excessive irrigation may leach nutrients from the active rootpattern. system. This may also reduce plant growth.Example As an example, consider drip irrigated tomatoes on 6-ftcenter beds, grown under plastic mulch production systemin the Central West area (sandy soils). For plants in growthStage 5 the crop coefficient is 0.85 (Table 10). If this periodFigure 4. Crop coefficient of drip irrigated tomato and strawberry.
Chapter 3: Principles and Practices of Irrigation Management for Vegetables Page 27 Table 11. Maximum water application (in gallons per acre and in gallons/100 lfb) in one irrigation event for various production systems on sandy soil (available water holding capacity 0.75 in/ft and 50% soil water depletion). Split irrigations may be required during peak water requirement. Gal/100ft to wet depth of 1.5 ft Gal/acre to wet depth of 1.5 ft Gal/100ft to wet depth of 1 ft Gal/100ft to wet depth of 2 ft Gal/acre to wet depth of 1 ft Gal/acre to wet depth of 2 ft Bed length (100 lbf/a) Wetting width (ft) Bed spacing (ft) Vegetable crop 1.0 24 36 48 4 Lettuce, strawberry 109 2,600 3,800 5,100 5 Cantaloupe 87 2,100 3,100 4,100 6 Broccoli, okra, cabbage, pepper, cauliflower, summer squash, pumpkin (bush), eggplant, Tomato 73 1,700 2,600 3,500 8 Watermelon, pumpkin (vining) 55 1,300 1,900 2,600 1.5 36 54 72 4 Lettuce, Strawberry 109 5 Muskmelon 87 3,800 5,800 7,600 6 Broccoli, okra, cabbage, pepper, cauliflower, summer squash, pumpkin (bush), eggplant, tomato 73 3,100 4,700 6,200 8 Watermelon, pumpkin (vining) 55 2,600 3,900 5,200 1,900 3,000 3,900
Chapter 4. 2012-2013Nematodes and Their ManagementJ.W. Noling BIOLOGY & LIFE HISTORY Plant parasitic nematodes are microscopic roundwormswhich live in the soil and attack the roots of plants. Crop Most species of plant parasitic nematodes have a rela-production problems induced by nematodes therefore tively simple life cycle consisting of the egg, four larvalgenerally occur as a result of root dysfunction, reducing stages and the adult male and female. Development ofrooting volume and foraging and utilization efficiency of the first stage larvae occurs within the egg where the firstwater and nutrients. Many different genera and species of molt occurs. Second stage larvae hatch from eggs to findnematodes can be important to crop production in Florida. and infect plant roots or in some cases foliar tissues. HostIn many cases a mixed community of plant parasitic finding or movement in soil occurs within surface filmsnematodes is present in a field, rather than having a single of water surrounding soil particles and root surfaces.species occurring alone. In general, the most widespread Depending on species, feeding will occur along the rootand economically important nematode species include the surface or in other species like root-knot, young larvalroot-knot nematode, Meloidogyne spp., and sting nema- stages will invade root tissue, establishing permanent feed-tode, Belonolaimus longicaudatus. The host range of these ing sites within the root. Second stage larvae will then moltnematodes, as with others, includes most if not all of the three times, to become adult male or female. For most spe-commercially grown vegetables within the state (Table 1). cies of nematodes, as many as 50 to 100 eggs are producedYield reductions can be extensive but vary significantly per female, while in others such as root-knot, upwards ofbetween plant and nematode species. In addition to the 2,000 may be produced. Under suitable environmental con-direct crop damage caused by nematodes, many of these ditions, the eggs hatch and new larvae emerge to completespecies predispose plants to infection by fungal or bacterial the life cycle within 4 to 8 weeks depending on tempera-pathogens or transmit virus diseases, which contributes to ture. Nematode development is generally most rapid withinadditional yield reductions. an optimal soil temperature range of 70 to 80°F. Table 1. Plant parasitic nematodes known to be of economic importance to vegetable crops in Florida. Bean and Pea Sweet Potato Sweet Corn Leaf Crops Cucurbits Crucifers Eggplant Tomato Pepper Celery Potato Carrot Onion OkraNematodeRoot Knot x x x x x x x x x x x x xSting x x x x x x x x x x x x xStubby Root x x x x x x x x x xRoot Lesion xCyst xAwl x xStunt xLance xSpiral xRingDaggerBud and LeafReniform x x Page 29
Page 30 Vegetable Production Handbook SYMPTOMS then does the amount of damage and yield loss. In general, the mere presence of root-knot or sting nematodes suggests Typical symptoms of nematode injury can involve both a potentially serious problem, particularly on sandy groundaboveground and belowground plant parts. Foliar symp- during the fall when soil temperatures favor high levelstoms of nematode infestation of roots generally involve of nematode activity. At very high levels, typical of thosestunting and general unthriftiness, premature wilting and which might occur under double cropping, plants may beslow recovery to improved soil moisture conditions, leaf killed. Older transplants, unlike direct seed, may toleratechlorosis (yellowing) and other symptoms characteristic of higher initial population levels without incurring a signifi-nutrient deficiency. An increased rate of ethylene produc- cant yield loss.tion, thought to be largely responsible for symptom expres-sion in tomato, has been shown to be closely associatedwith root-knot nematode root infection and gall formation. FIELD DIAGNOSIS & SAMPLINGPlants exhibiting stunted or decline symptoms usuallyoccur in patches of variable growth rather than as a overall Because of their microscopic size and irregular fielddecline of plants within an entire field. distribution, soil and root tissue samples are usually required to determine whether nematodes are causing poor The time in which symptoms of plant injury occur is crop growth or to determine the need for nematode man-related to nematode population density, crop susceptibil- agement. For nematodes, sampling and management is aity, and prevailing environmental conditions. For example, preplant or postharvest consideration because if a prob-under heavy nematode infestation, crop seedlings or trans- lem develops in a newly planted crop there are currentlyplants may fail to develop, maintaining a stunted condition, no postplant corrective measures available to rectify theor die, causing poor or patchy stand development. Under problem completely once established. Nematode densityless severe infestation levels, symptom expression may and distribution within a field must therefore be accuratelybe delayed until later in the crop season after a number of determined before planting, to guarantee that a representa-nematode reproductive cycles have been completed on the tive sample is collected from the field. Nematode speciescrop. In this case aboveground symptoms will not always identification is currently only of practical value whenbe readily apparent early within crop development, but rotation schemes or resistant varieties are available forwith time and reduction in root system size and function, nematode management. This information must then besymptoms become more pronounced and diagnostic. coupled with some estimate of the expected damage to for- mulate an appropriate nematode control strategy. Root symptoms induced by sting or root-knot nema-todes can oftentimes be as specific as above ground Advisory or Predictive Sample: Samples taken tosymptoms. Sting nematode can be very injurious, causing predict the risk of nematode injury to a newly planted cropinfected plants to form a tight mat of short roots, assuming must be taken well in advance of planting to allow fora swollen appearance. New root initials generally are killed sample analysis and treatment periods if so required. Forby heavy infestations of the sting nematode, a symptom best results, sample for nematodes at the end of the grow-reminiscent of fertilizer salt burn. Root symptoms induced ing season, before crop destruction, when nematodes areby root-knot cause swollen areas (galls) on the roots of most numerous and easiest to detect. Collect soil and rootinfected plants. Gall size may range from a few spheri- samples from 10 to 20 field locations using a cylindricalcal swellings to extensive areas of elongated, convoluted, sampling tube, or if unavailable, a trowel or shovel. Sincetumorous swellings which result from exposure to multiple most species of nematodes are concentrated in the cropand repeated infections. Symptoms of root galling can in rooting zone, samples should be collected to a soil depth ofmost cases provide positive diagnostic confirmation of 6 to 10 inches. Sample in a regular pattern over the area,nematode presence, infection severity, and potential for emphasizing removal of samples across rows rather thancrop damage. along rows. One sample should represent no more than 10 acres for relatively low-value crops and no more than 5 acres for high-value crops. Fields which have different crops (or varieties) during the past season or which have DAMAGE obvious differences either in soil type or previous his- For most crop and nematode combinations the damage tory of cropping problems should be sampled separately.caused by nematodes has not been accurately determined. Sample only when soil moisture is appropriate for workingMost vegetable crops produced in Florida are susceptible the field, avoiding extremely dry or wet soil conditions.to nematode injury, particularly by root-knot and stingnematodes (Table 1). Plant symptoms and yield reductions Diagnostics on Established Plants: Roots and soilare often directly related to preplant infestation levels in cores should be removed to a depth of 6 to 10 inches fromsoil and to other environmental stresses imposed upon the 10 to 20 suspect plants. Avoid dead or dying plants, sinceplant during crop growth. As infestation levels increase so dead or decomposing roots will often harbor few nema-
Chapter 4: Nematodes Page 31todes. For seedlings or young transplants, excavation of CULTURAL PRACTICESindividual plants maybe required to insure sufficient quan-tities of infested roots and soil. Submission of additional Crop Rotationsamples from adjacent areas of good growth should also be For crop rotation to be effective, crops unsuitable forconsidered for comparative purposes. nematode infection, growth, or reproduction must be introduced into the rotation sequence. In most of Florida For either type of sample, once all soil cores or samples it is not uncommon to observe a multispecies communityare collected, the entire sample should then be mixed thor- of nematodes all occurring within the same field. Underoughly but carefully, and a 1 to 2 pint subsample removed these circumstances it may not be possible to find a rota-to an appropriately labeled plastic bag. Remember to tion or cover crop that will effectively reduce populationsinclude sufficient feeder roots. The plastic bag will prevent of all nematode pests, particularly if root-knot and stingdrying of the sample and guarantee an intact sample upon nematodes occur in combination In this case, crop rotationsarrival at the laboratory. Never subject the sample(s) to detrimental to root-knot, which is generally the most diffi-overheating, freezing, drying, or to prolonged periods of cult to control, should be selected. In some cases, resistantdirect sunlight. Samples should always be submitted imme- crop varieties are available which can be used within thediately to a commercial laboratory or to the University of rotation sequence to minimize problems to some species ofFlorida Nematode Assay Laboratory for analysis. If sample root-knot but not sting nematodes.submission is delayed, then temporary refrigeration is rec-ommended at temperatures of 40 to 60°F. Use of poor or nonhost cover crops within the rotation sequence, may in some cases offer an effective approach Recognizing that the root-knot nematode causes the for- to nematode control. Three leguminous cover crops adapt-mation of large swollen areas or galls on the root systems able for managing soil populations of sting or root-knotof susceptible crops, relative population levels and field nematode include hairy indigo (Indigofena hirsuta),distribution of this nematode can be largely determined American jointvetch (Aeschynomene americana) and sunnby simple examination of the crop root system for root hemp (Crotalaria juncea). Sunn hemp is a sub-tropicalgall severity. Root gall severity is a simple measure of the legume that when grown in Florida performs like a sum-proportion of the root system which is galled. Immediately mer annual, being widely resistant to a large group of plantafter final harvest, a sufficient number of plants should be parasitic nematodes. It is adapted to a wide range of soilscarefully removed from soil and examined to character- and performs better on poor sandy, well drained soils withize the nature and extent of the problem within the field. a pH from 5 to 7.5. Sorghum is also a popular cover cropIn general, soil population levels increase with root gall restoring large amounts of soil organic matter, but is aseverity. This form of sampling can in many cases provide good host for sting and stubby root nematode but not root-immediate confirmation of a nematode problem and allows knot. Most of the small grains commonly used as wintermapping of current field infestation. As inferred previously, cover crops in central and north Florida, such as rye, mil-the detection of any level of root galling usually suggests let, barley, wheat or oats, can support limited reproductiona nematode problem for planting a susceptible crop, par- of root-knot nematode. To avoid an increase in root-knotticularly within the immediate areas from which the galled populations, these crops should only be planted when soilplant(s) were recovered. temperatures are below 65°F, a threshold temperature for nematode activity. Cover crop rotations with some pasture- land grasses (particularly pangola digitgrass, and to some extent Bahia-grass, and bermuda grass) have significantly GENERAL MANAGEMENT CONSIDERATIONS reduced, but not eliminated, root-knot nematodes. In north Currently nematode management considerations include Florida, long term (6- to 9- year) pastureland rotationscrop rotation of less susceptible crops or resistant variet- allowed economic watermelon production within root-knoties, cultural and tillage practices, use of transplants, and infested fields. It should be recognized that as the croppreplant nematicide treatments. Where practical, these rotation period is shortened or eliminated, nematode prob-practices are generally integrated into the summer or win- lems will intensify accordingly. Other perennial legumester ‘off-season’ cropping sequence. It should be recognized currently under evaluation may play an important role inthat not all land management and cultural control practices future nematode management programs.are equally effective in controlling plant parasitic nema-todes and varying degrees of nematode control should be For cover crops to be most effective, stands must beexpected. These methods, unlike other chemical methods, established quickly and undesirable weeds which can servetend to reduce nematode populations gradually over time. as alternative hosts must be controlled. Given that manyFarm specific conditions, such as soil type, temperature, different weeds serve as alternative plant hosts to nema-and moisture, can be very important in determining wheth- todes (i.e. nutsedges), it may not be possible to manageer different cultural practices can be effectively utilized for root-knot nematode with crop rotation unless an integratednematode management. program to manage weeds is also considered and imple-
Page 32 Vegetable Production Handbookmented within the field. This may also require broadcast resistant varieties are currently available only for tomato,seeding of the cover crop rather than planted in widely pepper, southernpea, and sweet potato. In a resistant variety,spaced rows. With many cover crops, rapid stand establish- nematodes fail to develop and reproduce normally withinment has been a significant problem. Similarly, economic root tissues, allowing plants to grow and produce fruit evencrop rotation sequences are often further complicated by though nematode infection of roots occurs. Some crop yieldlack of crop management skills, specialized equipment to loss can still occur however, even though the plants aregrow and harvest the crop, or by the lack of closely located damaged less and are usually significantly more tolerant ofprocessing facilities or markets. In some cases other mea- root-knot infection than that of a susceptible variety.sures should be considered such as fallowing which is usu-ally as efficient as crop rotation for reducing field infesta- In tomato, a single dominant gene (subsequently referredtions of nematodes. to as the Mi gene) has been widely used in plant breeding efforts and varietal development which confers resistance Fallowing to all of the economically importance species of root-knot Clean fallow during the off-season is probably the sin- nematode found in Florida, including Meloidogyne incog-gle most important and effective cultural control measure nita, M. arenaria, and M. javanica. Commercially resistantavailable for nematodes. When food sources are no longer fresh market varieties, climatically and horticulturallyreadily available, soil population densities of nematodes adapted for Florida are available as an effective nematodegradually decline with death occurring as a result of starva- management tactic in tomato. Unfortunately, in previoustion. Due to the wide host range of many nematode spe- research with resistant tomato varieties, the resistance cancies, weeds and crop volunteers must be controlled during fail as a result of the heat instability or apparent tempera-the fallow period to prevent nematode reproduction and ture sensitivity of the resistant Mi gene. For example, previ-further population increase. At least two discing operations ous research has demonstrated threshold soil temperaturesare generally required to maintain clean fallow soil condi- and incremental reductions in nematode resistance withtions during the interim period between crops. Fallowing each degree above 78°F, such that at 91°F tomato plants areby use of herbicides to deplete nematode populations is fully susceptible. This would suggest that in Florida, usea much slower process because the soil is not disturbed, of these varieties may be better suited for spring plantingsthereby subjecting nematodes from deeper soil layers to when cooler soil temperatures prevail.the drying action of sun and wind. The unfavorable effectsof fallowing on soil organic matter and soil structure are In pepper, two root-knot nematode resistant varietiesusually more than compensated for by the level of nema- (‘Carolina Belle’ and ‘Carolina Wonder’) were releasedtode control achieved and the resulting increase in crop from the USDA Vegetable Research Laboratory for com-productivity. When soil erosion is a potentially serious mercial seed increase in April 1997. Both varieties areproblem other measures should be considered. open pollinated, and homozygous for the root-knot nema- tode resistant N gene. Preliminary research has demon- Biological Control strated that these varieties confer a high degree of resis- At present there are no effective, commercially avail- tance to the root-knot nematode, however expression ofable, biological control agents which can be successfully resistance is heat sensitive. Further research is necessary toused to control nematodes. characterize the usefulness of these varieties under the high soil temperature conditions of Florida. Further research Biorational Compounds to incorporate the resistance genes into other commercial The active ingredients of these compounds can best available lines and varieties is also required. Like tomato,be described as either microbial agents or derived toxins, use of these varieties may have to be restricted to springplant extracts or dried plant products, or simple blends of plantings when cooler soil temperatures prevail.fatty acids, stabilized colloids, or secondary alcohols. Ingeneral, suitable and/or consistent nematode control and In addition, to problems of heat instability, the continu-crop yield enhancement has not been achieved with these ous or repeated planting of resistant plant varieties willproducts. Further research characterizing the utility of almost certainly select for virulent races of Meloidogynethese compounds under different environmental conditions, capable of overcoming the resistance. Therefore the dura-and the ways and means in which to increase their effec- tion and/or utility of the resistance may be time-limited. Intiveness is necessary. previous studies with resistant tomatoes, resistance break- ing nematode races develop within 1 to 3 years. Since new Plant Resistance races of the nematode can develop so rapidly, a system of Use of nematode-resistant crop varieties has not been integrated control usually mandates the rotation of resistantextensively evaluated in Florida, but is often viewed as the and non-resistant varieties to slow the selection process forfoundation of a successful integrated nematode manage- new virulent races. Recent trials in Florida have alreadyment program on all high value crops in which methyl bro- demonstrated the capacity of some species or races ofmide is currently used. Commercially available nematode- root-knot to reproduce and inflict damage upon a resistant
Chapter 4: Nematodes Page 33tomato variety. The results of this research have demon- tain and or produce organic acids with phytotoxic proper-strated that even with a resistant variety, which was dam- ties. Other studies have shown that soils amended withaged less than a susceptible variety, some consideration different sources of composted municipal wastes were dis-of initial soil population levels of the root-knot nematode ease suppressive as long as they were relatively fresh (< 6must be observed to minimize tomato yield losses. Given months), but as the composted municipal waste was aged,that significant yield losses can still occur, combined disease suppressiveness was lost. In other Florida studies,efforts to manage soil populations to low levels prior to application of composted municipal wastes at rates up toplanting must still be considered, particularly if tomatoes 120 tons per acre have not been shown to have pesticidalare planted as a fall crop. If this situation develops, the activity, but actually dramatically increased populations ofcombination of a nematicide and resistant variety may also nematodes and other disease organisms such as Fusariumcomprise an option to reduce nematode populations to and Phytopthora spp. Nematode population increases wereacceptable levels. directly related to increases in plant growth and root sys- tem size with amendment application rate. Soil Amendments Many different types of amendments and composted Recent studies in Florida have been conducted to deter-materials have been applied to soil to suppress popula- mine the extent to which increasing application rates oftions of plant parasitic nematode and improve crop yield a municipal solid composted waste affect the ability ofand plant health. Animal manures, poultry litter, and disk- tomato plants to tolerate root infection by species of root-incorporated cover crop residues are typical examples of knot nematode (Meloidogyne spp.) These studies showedsoil amendments used in agriculture to improve soil quality that in a sandy soil, poor in organic matter content (lessand as a means for enhancing biocontrol potential of soil. than 2%), tomato yields could be increased significantlySome amendments which contain chitin and inorganic with soil amendments in both nematode free or nematodefertilizers that release ammoniacal nitrogen into soil sup- infested soil. The impact of the root-knot nematode onpress nematode populations directly and enhance the selec- tomato yield was effectively constant however, suggestingtive growth of microbial antagonists of nematodes. More that application of the soil amendment did not enhance therecently, composted municipal wastes and sludges have ability of tomato plants to tolerate infection by the root-been used to amend soil to improve soil fertility, organic knot nematode. Much of the previous and ongoing researchmatter content, water holding capacity, nutrient retention, in Florida also seems to indicate that the major effects ofand cation exchange capacity. soil amendments to crop yields appear to be less related to nematode or soil pathogen control than to enhanced plant Suppression of soilborne pathogens via the incorpo- nutrition and nutrient and water availability.ration or simple mulching of composted amendmentsis reputedly based on enhanced microbial activity and It is not clear at this time and preliminary stage ofincreased numbers of antagonists generated by decompo- university field research whether benefits to crop growthsition of the amendment in soil. Soils with a diversity of after the initial crop following soil amendment applica-beneficial microorganisms are more suppressive to patho- tion can be expected. Recent studies showed no responsegens than soils with little or no biological diversity. Other in second crop tomato yields (double crop) followingpossible mechanisms for pathogen suppression by com- amendment application rates from 15 to 120 tons per acre.posts include direct inhibition of the pathogen or reduced Disappearance of nutrients and soil organic matter contentinfectivity of the organisms into the plant host. Population appears to be very rapid in the hot, moist soils of Florida.increases of beneficial organisms in soil appears to be the Reapplication of the amendments may have to be madedirect result of environmental changes brought about by on at least an annual basis to sustain crop growth andthe amendments after addition to soil. This suggests that to yield benefits. In summary, the high rates of applicationsustain soil suppressiveness, amendments must be periodi- (tons/acre) and attendant costs required for crop responsecally reapplied to maintain the soil environment conducive and nematode control for many different types of organicto antagonists. amendments, and the apparently rapid losses of the materi- als in soil appears to restrict use of these materials primar- The level to which soilborne pest and disease control ily to homeowner or small farm operations at this time.can be achieved is not only related to the type of material However, with additional research and advances in appli-but to the age of the compost. Nematode and disease sup- cation technology and use efficiency, use of soil amend-pression has been repeatedly demonstrated with composted ments may become an integral component of Florida cropmunicipal yard wastes containing significant quantities production systems.of tree bark. If the compost is immature, the product maynot only be difficult to handle and have an offensive odor, Floodingbut may contain salts and metabolites toxic to plants. For Extended periods of flooding suppresses nematode pop-example, weed suppression has been demonstrated with ulations. Alternating 2-to-3-week cycles of flooding andsome types of immature composted materials which con- drying are more effective than long, continuous flooding
Page 34 Vegetable Production Handbookcycles. At present, only limited areas within the state are coupling solarization with other chemical or nonchemicalsituated to take advantage of flooding as a viable means approaches. For example, the combined use of soil solar-of nematode control. Given the growing concern about ization with a nematicide has improved nematode controlaquifer depletion, salt water intrusion, and water use inef- and crop yield. In addition, use of virtually impermeable,ficiencies, it seems unlikely that Florida water management photo-selective plastic mulches may also complement lowofficials will continue to permit flooding within these areas dose fumigant treatments to reduce weed germination andin the future. growth in the event of extended periods of cloud cover occurring during the solarization regime. At this time, fur- Soil Solarization ther research is needed demonstrating soil solarization pest Soil solarization is a nonchemical technique in which control activity and consistency in the various geographicaltransparent polyethylene film is laid over moist raised beds regions of Florida where vegetable crops are grown.for a 6-to-12-week period to heat noncropped soils to tem-peratures lethal to nematodes and other soil-borne patho- Other Cultural Practicesgens. Soil temperatures are magnified due to the trapping Other cultural measures which reduce nematode prob-of incoming solar radiation under the clear, polyethylene lems include rapid destruction of the infested crop rootpanels. To be effective, soils must be wetted and main- system following harvest. Fields which are disced as soontained at high soil moisture content to increase the suscep- as possible after the crop is harvested will not only preventtibility (thermal sensitivity) of soil borne pests and thermal further nematode population growth but subject existingconductivity of soil. Wet mulched soils increase soil tem- populations to dissipation by sun and wind. Use of nema-peratures due primarily to the elimination of heat loss by tode free transplants is also recommended since directevaporation and upward heat convection, in addition to a seeded plants are particularly susceptible since they aregreenhouse effect by prohibiting dissipation of radiation vulnerable to injury for a longer duration, during an early,from the soil. At the end of the solarization period the clear but critical period of crop development. Since nematodesplastic is painted with a white or black latex paint to allow can be carried in irrigation water that has drained from ancontinued use of the plastic as a mulch cover for the pro- infested field, growers should avoid use of ditch or pondduction of vegetables on raised beds. waters for irrigation or spray mixtures. In most cases, a combination of these management practices will substan- The most successful use of soil solarization appears to tially reduce nematode population levels, but will rarelyoccur in heavier (loamy to clay soils) rather than sandy bring them below economically damaging levels. This issoils. Soils with poor water holding capacity and rapid especially true of lands which are continuously planted todrainage can significantly inhibit heat transfer to deeper susceptible crop varieties. In these cases some form of pes-soil horizons. Loss of pest control is directly correlated ticide assistance will still usually be necessary to improvewith soil depth. The depth to which lethal temperature can crop production.be achieved (6 to 8 inches) is also dependent on the inten-sity and duration of sunlight and ambient temperature. Atpresent, the only time to consider soil solarization for pest CHEMICAL CONTROLcontrol is during our hot, summer and early fall months,which fortunately are ‘off-season’ in most peninsular Nonfumigant NematicidesFlorida vegetable row crops. Unfortunately, our summers All of the nonfumigant nematicides (Table 2) currentlyare also our wettest period of the year with frequent after- registered for use are soil applied, with the exception ofnoon rain showers which have a cooling effect on the soil. Vydate, which can also be applied foliarly. They must be incorporated with soil or carried by water into soil to be Many different pests have been suppressed and or con- effective. These compounds must be uniformly appliedtrolled by soil solarization, particularly within arid environ- to soil, targeting the application toward the future rootingments with intense sunshine, and limited cloud cover and zone of the plant, where they will contact nematodes or, inrainfall. Soil solarization can also be effective in a subtrop- the case of systemics, in areas where they can be readilyical environment. Plant parasitic nematodes have generally absorbed. Placement within the top 2 to 4 inches of soilproved to be more difficult to control with soil solarization, should provide a zone of protection for seed germination,as have some weed pests such as crabgrass and purslane in transplant establishment, and protect initial growth ofa central Florida study. The results of preliminary experi- plant roots from seeds or transplants. Studies performedments are also suggesting the potential for selection pres- in Florida and elsewhere to evaluate non-fumigant nema-sures towards a buildup of heat tolerant individuals which ticides have not always been consistent, either for control-may serve to reduce soil solarization efficacy after repeated ling intended pests or for obtaining consistent economicuse as a nematode control tactic. returns to the grower, particularly when compared with conventional preplant mulched fumigation with methyl In some studies, effective use of solarization for nema- bromide or other broadspectrum fumigants. As the nametode control has required an integrated systems approach, implies, they are specific to nematodes, requiring integrat-
Chapter 4: Nematodes Page 35ed use of other cultural or chemical pest control measures. ment in tomato yields relative to plants maintained nema-Many are reasonably mobile and are readily leached in our tode free.sandy, low organic matter soils, thus requiring special con-sideration to irrigation practices and management. Fumigant Nematicides In Florida, use of broadspectrum fumigants (Table 3) Nematode management must be viewed as a preplant effectively reduces nematode populations and increasesconsideration because once root infection occurs and plant vegetable crop yields, particularly when compared withdamage becomes visible it is generally not possible to nonfumigant nematicides. Since these products must dif-resolve the problem completely so as to avoid potentially fuse through soil as gases to be effective, the most effec-significant yield losses. Experiments have been conducted tive fumigations occur when the soil is well drained,to evaluate the extent to which tomato plant growth and in seedbed condition, and at temperatures above 60°F.yield could be ‘rescued’ from root-knot nematode via early Fumigant treatments are most effective in controlling root-detection and treatment by post plant applications of the knot nematode when residues of the previous crop arenonfumigant nematicide, Vydate (oxamyl). The results of either removed or allowed to decay. When plant materialsthese experiments clearly showed that it was not possible have not been allowed to decay, fumigation treatmentsto completely resolve the problem and avoid tomato yield may decrease but not eliminate populations of root-knotlosses with post plant applications of Vydate. This was nematodes in soil. Crop residues infested with root-particularly obvious in tomato yield responses with foliar knot nematode may also increase soil populations to theapplications of Vydate attempting to resolve a soilborne extent that significantly higher rates of application mayproblem. If an attempt is going to be made to rescue the be required to achieve nematode control. To avoid thesecrop, the sooner the nematode problem is recognized and problems, growers are advised to plan crop destructionsoil applications of Vydate started, the greater the improve- and soil cultivation practices well in advance of fumiga- tion to insure decomposition of plant materials before attempting to treat the soil. Table 2. Non-Fumigant Nematicides Registered for Vegetable Crop Use in Florida For over 40 years, Florida producers of many high value fruit and vegetable crops have relied upon methyl Non-Fumigant Nematicides bromide soil fumigation to resolve their soilborne pest andVegetable Mocap Counter Vydate disease. In 1991, methyl bromide was detected in signifi-Beans * cant concentration within the earth’s stratosphere. In sub- sequent studies, it was shown to catalyze the destructionCarrots * of ozone, and determined to be a significant contributor toCelery * stratospheric ozone depletion, thinning, and the creation ofCorn, sweet * * an ozone hole over Antarctica. After being classified as aCabbage * Class I ozone depleting chemical in 1993, methyl bromide was mandated by the Clean Air Act of 1990 for eventualBrussels sprouts phase-out from production and agricultural use. After moreCucumber * * than a decade long regulatory struggle with numerousMelons * reprieves, the final phase-out date for methyl bromide pro-Squash * duction, importation, and use within the U.S. proceeded asOkra scheduled to January 1, 2005. As a grandfather clause, it is still possible to continue to use methyl bromide suppliesPotatoes * * produced prior to January 1, 2005, but only on the fourPotatoes, sweet * * currently defined ‘critical use exempted’ crops of tomato,Eggplant * pepper, eggplant and strawberry.Tomato * For tomato, pepper, eggplant and strawberry, contin-Pepper * ued post phase-out availability is now driven by a moreStrawberry complex process involving the use of both remaining, preThis information was compiled as a quick reference for the commercial Florida 2005 produced commercial stocks of methyl bromide, asvegetable grower. The mentioning of a chemical or proprietary product in this publi- well as those derived from new production made availablecation does not constitute a written recommendation or an endorsement for its use only through annual award of a Critical Use Exemption (CUE). The CUE is a rather complicated, national andby the University of Florida, Institute of Food and Agricultural Sciences, and doesnot imply its approval to the exclusion of other products or practices that may besuitable. Products mentioned in this publication are subject to changing State and international regulatory process. Simplistically described,Federal rules, regulations and restrictions. Additional products may become avail- the CUE represents a U.S.A. request for continued useable or approved for use. Growers have the final responsibility to guarantee that of methyl bromide that is submitted to and approved byeach product is used in a manner consistent with its label. an international United Nations and Montreal Protocol
Page 36 Vegetable Production Handbookauthority, which substantiates the need for continuing use or two. Further information regarding the methyl bromideof methyl bromide for crops and farming enterprises in CUE process, diminishing supply and transition strategywhich “no technically or economically feasible alterna- to alternatives can be found in a subsequent chapter of thistive to methyl bromide is shown to exist”. We have been production guide.fortunate in that approved CUE levels for new productionof methyl bromide have been awarded for calendar years Ultimately, the loss of methyl bromide in the U.S.A2005 through 2012. A CUE request for continued use of will create a void for Florida growers in the chemicalmethyl bromide for 2013 and 2014 has also been submit- arsenal currently used for soilborne pest and disease con-ted for consideration and approval. Each year the approved trol. This fact is made quite clear from a decade reviewlevel of new production combined with supply of existing of recent field research trials conducted in Florida whichstocks is reduced which with such reduced current avail- show that no single, equivalent replacement (chemical orability will ultimately force Florida growers to transition nonchemical) currently exists which exactly matches theto alternatives strategies completely in the following year broadspectrum efficacy of methyl bromide. In preparation Table 3. Broadspectrum Fumigant Nematicides Registered for Vegetable Crop Use in Florida Formulation Methyl Bromide3 To Chloropicrin2 OTHER FUMIGANTS 50 0 Methyl2 Metam2 Metam2 Pic-Clor1 60 Telone1,2 Telone1 C35 DMDSCrop/Use 50 100 Iodide Sodium Potassium Pic-Clor1 60EC Telone1 II C17 Telone1 Inline + PIC4Asparagus * * * * * *Broccoli * * * * * *Cauliflower * * * * * *Cucumber * * * * * * * *Eggplant * * * * * * * * *Muskmelon * * * * * * *Onions (bulb) * * * * * *Onions * * * * * * *Peppers * * * * * * * * *Tomato * * * * * * * * * *Sweet potato * * * * * * *Vegetable * * * * * *Strawberry * * * * * * * * * *Plant Bed * * * * * * *Seed Bed * * * * * * *1 rop recommendations for Pic-Clor 60, Pic-Clor 60EC, Telone II, Telone C17, Telone C35, or Telone Inline do not apply to the Homestead, Dade County production region of C south Florida where soil types and water tables currently prohibit product use. Other supplementary labeling with additional county or soil and use restrictions may apply for the Telone components of these formulations.2 urrently completing EPA Fumigant Reregistration (expected Spring 2012), with significant new label restrictions for buffer zones, mandatory Good Application Practices C (GAP’s), Fumigant Management Plans (FMP), and other new restrictions and requirements.3 critical use exemption (CUE) for continuing use of methyl bromide for tomato, pepper, eggplant and strawberry has been awarded for calendar year 2012. Specific certified A uses and labeling requirements for existing stocks and CUE acquired methyl bromide must be satisfied prior to grower purchase and use in these crops. Formulation availability is subject to change.4 Dimethyl Disulfide (DMDS, Paladin™) has now received both U.S. Federal EPA and state registration and is now just entering the commercial marketplace. Its use has not been broadly tested in Florida but has proved very effective against nematode and disease, and for many weeds. Provides excellent control of nutsedge but only poor to fair control of annual grasses and requires the use of a separately applied herbicide for adequate control. Crops labeled include tomatoes, peppers, eggplants), cucurbit crops (cucumber, squash and melons), strawberries, blueberries, field-grown ornamentals, and forest nursery stock where plastic tarp is used for fumigation.This information was compiled as a quick reference for the commercial Florida vegetable grower. The mentioning of a chemical or proprietary product in this publication does notconstitute a written recommendation or an endorsement for its use by the University of Florida, Institute of Food and Agricultural Sciences, and does not imply its approval to theexclusion of other products or practices that may be suitable. Products mentioned in this publication are subject to changing State and Federal rules, regulations and restrictions.Additional products may become available or approved for use. Growers have the final responsibility to guarantee that each product is used in a manner consistent with its label.
Chapter 4: Nematodes Page 37for the ultimate phase-out and loss of methyl bromide, uni- has demonstrated to provide excellent control of nutsedgeversity research programs within Florida have continued but only poor to fair control of annual grasses and thusto identify and evaluate more robust strategies which mini- requires the use of a separately applied herbicide for ade-mize cropping system impacts, accounting for a diverse quate weed control.range of pest pressures and environmental conditions.Based on summary and comparison of methyl bromide All of the soil fumigants are nearing completion of aalternative chemical trial results in Florida since 1994, long reregistration process, culminating in the phase in ofTelone (1,3-Dichloropropene) plus Chloropicrin) applied the new labels over a two year period. With Phase 1, majoreither separately or coformulated as Telone C35 (1.3-D changes in the federal labels for all fumigant productsplus 35% Chloropicrin) or Pic-Clor 60 (1,3-D plus 59% began to appear January 1, 2011, with the second roundChloropicrin) in combination with a separately applied her- of new labels changes expected after Phase 2 is completedbicidal compound or MITC generating fumigant for weed during late spring 2012. With Phase 1, specific require-control, has been identified as the best chemical alternative ment for personnel protective equipment (PPE) was greatlyreplacement for methyl bromide for some vegetable row reduced, particularly for field workers with no liquidcrops such as strawberry and tomato. In strawberry, use of contact potential, and where sensory irritation is not expe-formulations of 1,3-D with higher proportionate levels and rienced by field workers during fumigant application. Forrates of application of chloropicrin have not consistently example, Phase 1 label changes now require that full faceresulted in effective sting nematode control when com- respirator must only be worn by all personnel in the fieldpared with Telone C35 or Telone Inline. if a handler in the field complains of sensory irritation and the certified applicator decides to remain in the field and This has also been repeatedly demonstrated in large to continue fumigation within the application block. Thescale, commercial field trials around the state. In these new Phase 1 labels require certified applicators to providestudies, use of Telone and Chloropicrin in combination certification that all handlers present for the days fumiga-with a herbicide treatment, including mini-coulter applica- tion have received safety information for handlers of pes-tion of metam sodium or potassium to the bed top prior ticide soil fumigants within the past year. Phase 1 labelsto installing the plastic mulch, generally resulted in near also now require certified applicators to complete fumigantequivalent yields to that of methyl bromide. With repeated management plans (FMP), including details of the differ-long term use, or under conditions of high pest pressures ent fumigants used, application rates, method of fumigant(weeds, nematodes, disease), other IPM practices might application and plastic mulch used, personal details ofalso be required and combined to achieve adequate control all handlers involved, soil and environmental conditionsand economic crop productivity. For example, prebed treat- present and any mandatory good agricultural practicesments of Telone C35 (35 gal/A) or Telone II (12 gal/A) that were required for the application. The new Phase 1followed by an additional in-bed application of chloro- labels also require applicators to develop a written Postpicrin (150 lb/A) followed by metam sodium application Application Summary report which will describe and docu-(75 gal/A) to the bed top has been required for effective ment any complaints from neighbors or field workers, anyweed and disease control in pepper. In combination with incidents or accidents which were reported or occurred,Telone, Telone C35 or Chloropicrin, growers are also and whether any significant deviation from the day andencouraged to use only high barrier, metalized, or virtually site specific FMP occurred. In all cases, the grower has theimpermeable mulch films (VIF), particularly those with final responsibility to insure that the label is consulted andEPA approved buffer zone reducing credit. With use of that each product is used legally according to the label.the more impermeable mulches, fumigant rates have been The new phase 2 label restrictions will require certifiedreduced as much as 25 to 40% from maximum labeled applicators to impose buffer zones around treated fields.application rates without loss of pest control or crop yield Buffer zone distances will be determined by methods andin many studies. Given the potential variability, growers rates of fumigant application per treated acre and to howshould consider their own small scale field trials to deter- many acres will be treated per day. After EPA completionmine the degree to which rates reductions of the different of fumigant reregistration (expected Spring 2012), EPAfumigants with high barrier mulches is possible. Due to will only recognize use of specific high barrier or trueuse restrictions for all Telone products in Dade County, VIF mulch films where film permeabilities (mass transfereither metham sodium or metham potassium at 75 and 60 coefficients) to the different fumigant gases have beengallons per treated acre respectively, in combination with measured and meet EPA approved emission reductions toshank injections of chloropicrin (150 pound per treated qualify for buffer zone reducing credits.acre) and appropriate herbicide(s) are currently defined asthe best alternatives to methyl bromide. Dimethyl disul- As with any new technology, prebed applications offide (DMDS; Paladin ™), the newest entry to registered Telone or Telone C35 by growers will require some newfumigants in Florida, has demonstrated good to excellent field equipment and changes in application procedurecontrol of nematodes and disease when coapplied with and timing. Deep placement of Telone C-35 is not only21% (wt/wt) chloropicrin (PIC). DMDS + PIC (60 gal/A) a requirement of the pesticide label but is essential for
Page 38 Vegetable Production Handbookprolonged fumigant retention in soil. Unfortunately, deep SUMMARYinjection of prebed applications of Telone C-35 to a depthof 10 to 12 inches can be difficult to achieve because of In summary, nematode control measures can be con-the presence of a compacted traffic layer in most fields. To veniently divided into two major categories: cultural andenhance treatment efficacy, growers should consider tillage chemical. None of these measures should be relied uponoperations which destroy the traffic pan to ensure fumigant exclusively for nematode management. Rather, when prac-diffusion within the bed and soil profile with deep place- tical and economics permit, each management procedurement of Telone. Federal and state regulations currently should be considered for use in conjunction with all otherlimit the application of any Telone containing product available measures for nematode control and used in anwithin 100 feet of any occupied structure, dwelling, or integrated program of nematode management.drinking water well. Unavoidably, some uncontrollableenvironmental factors such as temperature and rainfall can In addition, to nematodes, many other pests can causeaffect the performance of fumigant treatment and plant- crop damage and yield losses which further enforces theback scheduling. Growers must therefore plan accordingly development of an overall, Integrated Pest Managementto account for any unforeseen delays in fumigant dissipa- (IPM) program, utilizing all available chemical and non-tion from soil and to avoid potential phytotoxic impact to chemical means of reducing pest populations to subeco-crops. nomic levels. An IPM approach further requires that grow- ers attempt to monitor or scout fields for pest densities at All of the fumigants are phytotoxic to plants and as a critical periods of crop growth.precautionary measure should be applied at least 3 weeksbefore crops are planted. When applications are made inthe spring during periods of low soil temperature, theseproducts can remain in the soil for an extended period, thusdelaying planting or possibly causing phytotoxicity to anewly planted crop. Field observations also suggest rainfallor irrigation which saturates the soil after treatment tendsto retain phytotoxic residues for longer periods, particularlyin deeper soil layers. Unless growers are prepared to acceptplanting delays or stand losses, irrigation to the mulchcovered beds should be discontinued for at least one weekfollowing fumigant application to allow fumigant diffusionand dissipation through open air passages in soil. In the coming post-methyl bromide era, successful fumi-gation programs with the alternatives will rely more onfield preparation, new technologies for fumigant deliveryand application, and other good agricultural - crop produc-tion practices (GAP’s) than simply with fumigant selectionand application. With methyl bromide, variations in soiltilth, temperature, or moisture seldom played a promi-nent role in defining or lowering its overall performance.However, in order to achieve maximum efficacy with afumigant alternative program, it will be necessary to payattention to every detail involved in field preparation, fumi-gant application, formulation selection, and environmentalcondition during and immediately following soil applica-tion. Early crop destruction, a key foundation principal ofIPM, will also become a more integral component of soilborne pest management programs. Methyl bromide was avery flexible and forgiving fumigant, achieving satisfac-tory pest control and crop yield response under a variety ofconditions. Clearly, the consistency and flexibility of thealternatives are not as evident or as forgiving.
Chapter 5. 2012-2013Weed ManagementP.J. Dittmar and A.W. MacRae Weeds reduce yield and quality of vegetables through Mechanical Controldirect competition for light, moisture, and nutrients as well Mechanical control includes field preparation by plow-as by interference with harvest operations. ing or discing, cultivation, mowing, hoeing, and hand pull- ing of weeds. Mechanical control practices are among the Early season competition is most critical and a major oldest of weed management techniques.emphasis on control should be made during this period.Common amaranth reduces yields of lettuce, watermelon, Weed control is a primary reason for preparing land forand muskmelon at least 20% if allowed to compete with crops planted in rows. Seedbed preparation by plowing orthese crops for only the first 3 weeks of growth. Weeds can discing exposes many weed seeds to variations in light,be controlled, but this requires good management practices temperature, and moisture. For some weeds, this processin all phases of production. Because there are many kinds breaks weed-seed dormancy, leading to early season con-of weeds, with much variation in growth habit, they obvi- trol with herbicides or additional cultivation.ously cannot be managed by a single method. Cultivate only deep enough in the row to achieve weed The incorportation of several of the following manage- control; deep cultivation may prune crop roots, bring weedment practices into vegetable production practice increases seeds to the surface, and disturb the soil previously treatedthe effectiveness for controlling weeds. with a herbicide. Follow the same precautions between rows. Crop Competition An often overlooked tool in reducing weed competition When weeds can be controlled without cultivation, thereis to establish a good crop stand, in which plants emerge is no advantage to cultivating. In fact, there may be disad-and rapidly shade the ground. The plant that emerges first vantages such as drying out the soil surface, bringing weedand grows the most rapidly is the plant that will have the seeds to the surface, and disturbing the root system of thecompetitive advantage. Utilization of good production crop.management practices such as fertility, well-adapted vari-eties, proper water control (irrigation and drainage), and Mulchingestablishment of adequate plant populations is very helpful The use of polyethylene mulch increases yield and earli-in reducing weed competition. Everything possible should ness of vegetables. The proper injection of fumigants underbe done to insure that vegetables, not weeds, have the the mulch will control nematodes, soil insects, soil-bornecompetitive advantage. diseases, and weed seeds. Mulches act as a barrier to the growth of many weeds. Nutsedge, however, is one weed Crop Rotation that can grow through the mulch. If the same crop is planted in the same field year afteryear, there usually will be some weed or weeds favored by Preventionthe cultural practices and herbicides used on the crop. Preventing weeds from infesting or reinfesting a field should always be considered. Weed seed may enter a field By rotating to other crops, the cultural practices and in a number of ways. It may be distributed by wind, water,herbicide program are changed. This often reduces the machinery, in cover crop seed and other ways. Fence rowspopulation of specific weeds which were tolerant in the and ditch banks are often neglected when controlling weedsprevious cropping rotation. Care should be taken, however, in the crop. Seed produced in these areas may move intoin not replanting vegetables back into soil treated with a the field. Weeds in these areas can also harbor insects andnon-registered herbicide. Crop injury as well as vegetables diseases (especially viruses) that may move onto the crop.containing illegal residues may result. Check the labels forplant back limitations before application and planting rota- It is also important to clean equipment before enteringtional crops. fields or when moving from a field with a high weed infes- tation to a relatively clean field. Nutsedge tubers especially are moved easily on discs, cultivators, and other equipment. Page 39
Page 40 Vegetable Production Handbook Herbicides ESTIMATED EFFECTIVENESS OF RECOMMENDED Properly selected herbicides are effective tools for HERBICIDES ON SELECTED COMMON WEEDS INweed control. Herbicides may be classified several ways, FLORIDA VEGETABLESdepending on how they are applied and their mode ofaction in or on the plant. Generally, herbicides are either Identifying the weed problems and selecting appropriatesoil applied or foliage applied. They may be selective or control methods are essential steps in designing or modify-non-selective, and they may be either contact or translo- ing a weed control program. Knowing the weed speciescated through the plant. For example, paraquat is a foliar that infest the fields is also important in selecting the cor-applied, contact, non-selective herbicide, while atrazine rect herbicide that is effective for specific weed problesm.usually is described as a soil-applied, translocated, selec- Generally, for preplant and preemergence applications,tive herbicide. the weed problem must be antifcipated since weeds have not emerged at the time of application. This can be done Foliage-applied herbicides may be applied to leaves, by observing the field in the previous seson and recordingstems, and shoots of plants. Herbicides that kill only those those weeds which are present and in what areas of theparts of the plants, which the spray touches, are contact field they occur. These weed maps can be very useful theherbicides. Those herbicides that are taken into the plant next season in refreshing your memory and making deci-and moved throughout the plant are translocated herbi- sions on which herbicides to purchase. Once weed prob-cides. Paraquat is acontact herbicide while glyphosate or lems have been determined, the following tables can besethoxydim are translocated herbicides. helpful in determining the herbicide which is most effec- tive for control of those weeds. For foliage-applied herbicides to be effective, they mustenter the plant. Good coverage is very important. Most Table 1 and 2, estimating the effectiveness of controlfoliage applied herbicides either require the addition of a of certain herbicides, were developed from research data,specified surfactant or a specified formulation to be used herbicide labels, and the experience of research and exten-for best control. sion workers in Florida. The estimated effectivenss is based on recommended rates for vegetables in Florida and Soil-applied herbicides are either applied to the surface application procedures as specified by the labe. Herbicdeor incorporated. Surface-applied herbicides require rainfall effectiveness may vary due to soil type, environmentalor irrigation shortly after application for best results. Lack conditions (rainfall, temperatures, etc.), method and timeof moisture often results in poor weed control. of application, as well as size of weeds. Consult the herbi- cide label for specific information relating to crop use and Incorporated herbicides are not dependent on rainfall expected response of the herbicide in specific soil types.or irrigation and have generally given more consistent andwider-spectrum control. They do, however, require moretime and equipment for incorporation. CROP GROUPS Herbicides which specify incorporation into the soil The Environmental Protection Agency is authorized toimprove the contact of the herbicide with the weed seed establish tolerances for pesticide residues in raw agricul-and/or minimize the loss of the herbicide by volatilization tural commodities under section 408 of the Federal Food,or photodecomposition. Some herbicides, if not incorpo- Drug, and Cosmetic Act (FFDCA) ( 21 USC 34a). Croprated, may be lost from the soil surface. grouping regulations currently in effect enable establish- ment of tolerances for a group of crops based on residue Although most soil-applied herbicides must be moved data for certain crops that are representative. In otherinto the soil to be effective, the depth of incorporation into words, establishing tolerances for three specified crops inthe soil can be used to achieve selectivity. For example, if a group could also establish tolerances for pesticide usea crop seed is planted 2 inches deep in the soil and the her- on the remainder of the commodities of that group, whichbicide is incorporated by irrigation only in the top 1 inch may be up to 19 separate commodities.where most of the problem weed seeds are found, the croproots will not come in contact with the herbicide. If too Commodity groups or subgroups are specified in themuch irrigation or rain moves the herbicide down into the Federal Register. A proposed rule on the Revision of thecrop seed zone or if the herbicide is incorporated mechani- Crop Groups (40 CFR 180) is under consideration atcally too deep, crop injury may ensue. this time. To avoid confusion on specific commodities or groups that may be listed on labels, a brief summary is provided below:
Chapter 5: Weed Management Page 41 Beans and Peas spp (i.e. bitter melon, balsam pear, balsam apple, Chinese If the term bean appears on the label, the material may cucumber); and other varieites and/ or hybrids of thesebe applied to both Phaseolus and Vigna types of beans. species. Winter squash are consumed when the fruitThe Phaseolus beans include adzuki bean, field bean, kid- are mature and have a harder exterior to the fruit. Winterney bean, lima bean, moth bean, mung bean, pinto bean, squash includes butternut squash, calabaza, hubbardrice bean, runner bean, snap bean, tepary bean, urd bean, squash, acorn squash, and spaghetti squash.and wax bean. The Vigna beans include southern pea, cow-pea, asparagus bean, catiang, Chinese long bean, and yard Lettucelong bean. If the term beans is on the label, then the mate- Head lettuce only applies to crisp head varieties of let-rial may be applied to southern peas as well as snap beans. tuce. Leaf lettuce applies to all leaf lettuce types, includ-However, if the term green bean appears, the material may ing leaf lettuce, cos (Romaine) and the butterhead variet-be applied to only the green color snap bean, and not the ies. The term lettuce includes head and leaf lettuce, i.e.,wax types. Peas do not include southern peas but include all types except endive and escarole. Endive is a separateall Pisum species including English pea, edible-pod pea, tolerance group and includes endive and/or escarole.snowpea, sugar pea, dwarf pea, and Cajanus cajan, thepigeon pea. Brassica (cole) Leafy Vegetables The Brassica (cole) leafy vegetable includes two sub-groups. The first subgroup is head & stem brassica andincludes includes broccoli, Chinese broccoli, Brusselssprouts, cabbage, Chinese cabbage (napa), Chinese mus-tard cabbage, cauliflower, cavalo broccoli, and kohlrabi.The second subgroup is leafy brassica greens subgroupincluding broccoli raab, Chinese cabbage (bok choy), col-lards, kale, mustard greens, mustard spinach, and rapegreens. Fruiting Vegetable Crops Solanaceous vegetables such as tomato, pepper, andeggplant are included in the fruiting vegetable crop groups.Okra is also included in this crop group. Cucurbit Crops Cucurbit crops include cucumber, squash, watermelon,and muskmelon along with commodities falling underthese groups. Melons is a general term which designatesmuskmelon, including hybrids and/or varieties of Cucumismelo, and watermelon, including hybrids and/or varietiesof Citrullus spp. The term muskmelons includes hybrids and/or varietiesof Cucumis melo (including true cantaloupes, cantaloupe,casaba, Santa Claus melon, Crenshaw melon, honeydewmelon, honey balls, Persian melon, golden pershaw melon,mango melon, pineapple melon, and snake melon). Summer squash includes fruits of the gourd(Cucurbitaceae) family that are consumed when imma-ture; 100% of the fruit are edible either cooked or raw;cannot be stored once picked; have soft rinds which areeasily penetrated; and if seeds were harvested, they wouldnot germinate. Summer squash includes Cucurbita pepo(crookneck squash, straightneck squash, scallop squash,and vegetable marrow); Lagenaria spp (i.e. hyotan, cucuz-za); Lufa spp (i.e. hechima, Chinese okra); Momordica
Page 42 Vegetable Production HandbookTable 1. Estimated effectiveness of herbicides on selected broadleaf weeds in vegetables. Florida beggarweed Evening primrose Morningglories Florida pusley Lambsquarter Southern sida Parthenium Nightshade Amaranths Cocklebur Sicklepod Ragweed Purslane EcliptaHerbicidePREPLANT INCORPORATEDCommand F-G P-F G - - G - G-E E P - F-G P -Dacthal F-G P F-G - F F - G G P F - P FDevrinol F-G P G P P G-E P G-E G P P - P -Dual G P G-E G F-G G-E - G-G F P F F P GEptam G P G G P G-E - G G F P-G F F GPrefar F P F P P E - F-G F P P P P PPursuit G-E - E E E F - E E G-E G-E G P GSencor E G E G G-E G G E G G-E P G G GTreflan G-E P G F-G P E P G-E E P P P P PPREEMERGENCEAlanap G-E F G G F G - E G F F F P GAtrazine E G-E E G-E G-E E E E E G G E F-G G-ECallisto G-E F - - - - - G - F G G - NCCaparol G-E - - - - F-G - F-G G-E - F-G F-G - -Chateau G-E G-E G-E - G G-E - G-E G-E G G-E G-E G GCommand F-G P G - - G - G E P - F P -Curbit G P G - P E P G-E E P P P P PDacthal F-G P F-G - F F - G G P F - P FDevrinol F P G P P G P G G P P - P -Dual G F G G F G - F P P F F P GGoal E E E E G G G E E G G G F GKerb F-G - G - - G - E G-E F-G G - - -Lorox G F E - G E - E E F - G - FMatrix G-E G-E E E E - - E E - F G - -Prowl G-E P G - P G P E G P P P P -Pursuit G-E G-E E E P F - G-E G-E G-E G-E G P G*Sandea G-E G G G - F - G G F N G G GSencor G F E F-G G G G E G F P-F G G G
Chapter 5: Weed Management Page 43Table 1. Continued. Florida beggarweed Evening primrose Morningglories Florida pusley Lambsquarter Southern sida Parthenium Nightshade Amaranths Cocklebur Sicklepod Ragweed Purslane EcliptaHerbicidePOSTEMERGENCEAim E G E G G G - E G G E E G G-EAtrazine G-E F E G P G-E F-G G F-G G F F F-G -Basagran G G G G P F - - G F-G F-G G P GCallisto E G-E - - - G - G-E - F G G G NChateau E G - - G F-P - G-G F-G F-G G F-G F-G F-GCobra E G-E - E E G-E - F-G G G-E E G F-G GDiquat E G E E G-E G E E G F-G G G G GEnquik E G E E E G G F-G G F G G G GFusilade N N N N N N N N N N N N N NGramoxone E G E E G-E G P E G F-G F G G GImpact G-E G-E - - - F-G - G - G E G-E - GLaudis E E - - - G - G-E N F G G-E F NLorox E G - - G G - E E F-G - G G GMatrix G G-E G G G G - P - G P G - -Poast N N N N N N N N N N N N N NPursuit E G G G - F - F-G P-F G G G P -Select N N N N N N N N N N N N N N*Sandea G G - F - P - P F G - F - -Sencor E G G F G G P G F-G P P F-G F FN = no control, P = below 60%, F = 60-80%, G = 80-90%, E = 90-100%, - = no data* Poor on livid amaranth.
Page 44 Vegetable Production HandbookTable 2. Estimated effectiveness of herbicides on selected grasses and sedges in vegetables. Grasses Sedges Broadleaf signalgrass Yellow nutsedge Purple nutsedge Bermuda grass Annual sedges Barnyardgrass Sprangletop Goosegrass Crabgrass PanicumsHerbicidePREPLANT INCORPORATEDCallisto - - F-G G G F-G - N N NChateau G - - G G G - N N NCommand E G-E E E E G-E - P P PDacthal G G F G G F - P P PDevrinol E E E E E G-E - P F FDual G G-E E E E G G P-G G G-EEptam E E G E E G-E - G-E G EPrefar G G G G G-E F-G - P P PPursuit F P F F F P-F P F-G G ESandea N N N N N N N G-F F-G GSencor G F-G G G-E G-E F-G - P P PTreflan E G G-E E E G - P P PPREEMERGENCEAlanap P P F F P P - P P PAtrazine F P F-G F F P P P P PCaparol F-G F-G F-G G F-G F - P P PCommand E E E E E E - P P PCurbit E G-E E E E G-E G P P PDacthal F-G F-G F G G F - P P PDevrinol E E E E E G-E - P-F F F-GDual E E E E E G-E G P-F F-G EGoal E P F F F P - P F GKerb G-E P G G-E G-E F-G - P P PLorox F-G - G G G F-G - F F FMatrix P P P P P P P P P PProwl E E E E E G-E E P P PPursuit F P F F F P-F P G G-E ESencor F F G G G-E P P P P PPOSTEMERGENCEAim P P P P P P P P P PAtrazine F-G F F F F F F P P PBasagran P P P P P P P P-F F-G G-E
Chapter 5: Weed Management Page 45Table 2. Continued. Grasses Sedges Broadleaf signalgrass Yellow nutsedge Purple nutsedge Bermuda grass Annual sedges Barnyardgrass Sprangletop Goosegrass Crabgrass PanicumsHerbicidePOSTEMERGENCECallisto - - G-F F-G F-G - - N N NCobra N N N N N N N N N N*Diquat E-G G E G-E G-E G G F-G F-G GEnquik P-F P-F P-F P-F P-F P-F - F F FFusilade E E E E E E E P P P*Gramoxone E E E E E E E F-G F-G GImpact G - - G G - - N N NLaudis G - G F-G G G-E - N N NLorox G F-G G G G G G F F F-GMatrix P P P P P P P P P -Poast E G-E E E G E E N N NPursuit F P P-F P F P-F P G-E G-E G-ESelect E G-E G-E G-E E E E N N NSandea N N N N N N N E E ESencor F P P-F F F-G P P P P PN = no control, P = below 60%, F = 60-80%, G = 80-90%, E = 90-100%, - = no data* Sedges and other perennial weeds will have initial burndown then regrowth occurs.
Chapter 6. 2012-2013Alternatives to Methyl Bromide Soil Fumigationfor Florida Vegetable ProductionJ. W. Noling, D. A. Botts and A. W. MacRae In 1991, climatic studies of historic concentrations of tinuing use of methyl bromide for tomato, pepper, egg-methyl bromide captured in polar ice showed increasing plant and strawberry has been awarded for calendar yearsamounts of the compound over the past several decades. In 2005 through 2012. CUE’s for these crops for 2013 aresubsequent studies, it was shown to catalyze the destruc- currently in the review and approval process at the inter-tion of ozone, and determined to be a significant contribu- national level. The reference baseline used for regulatorytor to stratospheric ozone depletion, thinning, and the cre- comparison is the use during the 1991 calendar year. Totalation of an ozone hole over Antarctica. After being classi- Critical Use Exemptions at the national level are reportedfied as a Class I ozone depleting chemical in 1993, methyl as percentages of this 1991 baseline. With each additionalbromide was mandated by the Clean Air Act of 1990 for year of CUE submission, the amount of new methyl bro-eventual phaseout from production and agricultural use. mide production awarded or allowed is generally less thanAfter a 13-year-long regulatory process with numerous the amount of methyl bromide awarded the previous yearshifts to the schedule for final regulatory action, the final and, more importantly, of the amount formally requestedphase-out date for methyl bromide production and impor- by the U. S. Government in its Critical Use Nominationtation, for use within the U.S. proceeded as scheduled on (Figure 1). Because of the diminishing level of existingJanuary 1, 2005. As with other ozone depleting substances commercial stocks, and significantly reduced allowancesregulated under the Montreal Protocol on Ozone Depleting for the production of new product, shortages in methylSubstances and the U. S. Clean Air Act, supplies of mate- bromide supply are becoming increasingly more apparent,rials manufactured and imported prior to the scheduled and are fully expected to become much more severe thanphase out continue to be legal to use as approved for only in previous years as we progress through the 2011 - 2012specifically exempted crops. cropping seasons. In tomato, pepper, eggplant, and strawberry, continued Florida growers, who have continued to rely on exist-post phase-out availability is now driven by a more com- ing and internationally approved CUE supplies of methylplex process involving the use of both remaining com- bromide, painfully recognize an increase in price, a futuremercial stocks of methyl bromide, as well as those from of diminishing supply, and the limits to which methylother new supplies made available only through award of bromide use rates can be reduced without loss of pesti-a Critical Use Exemption (CUE). The CUE process is a cidal efficacy and crop yield. Local competitive pressurescomplicated, national and international regulatory drivenprocedure. Simplistically described, the CUE is a processof documenting the need for continued use as describedby the collective research efforts of grower organiza-tions, University of Florida - IFAS research and extensionfaculty, as well as many other state and federal agencies.It culminates in a final document compiled by the U. S.Government of all such petitions nationwide that is submit-ted for review and approval by the Parties to the MontrealProtocol. The criterion for approval is the need for continu-ing use of methyl bromide for crops and farming enter-prises in which “no technically or economically feasiblealternative to methyl bromide is shown to exist”. Based on CUE petitions developed and submitted by Figure 1. tatistical projection of forced rates of adoption of alterna- S tives based on the CUE approved amounts of “new” methylthe Florida Fruit & Vegetable Association (FFVA), and bromide production and consumption. The projection isendorsed and supported by EPA, USDA, and the United based on assumptions of minimal “available Stocks”, 1991States State Department, a critical use exemption for con- use characteristics and 2005 base crop acreages. Page 47
Page 48 Vegetable Production Handbookalso led to Florida growers being reluctant to transition to To sustain availability, methyl bromide distributors arenew integrated pest management strategies which include again only currently providing formulations with increasedco-application of different fumigants and herbicides, and chloropicrin content, primarily a formulation of 50%adoption of other alternative cultural practices to achieve methyl bromide and 50% chloropicrin. This formulationpest control efficacy and crop yield response similar to that has not been well liked by Florida growers because of itsof methyl bromide. higher chloropicrin content and pest control shortcomings (particularly weeds). With limited supply and formulation Transition to the alternatives has also required growers availability, Florida growers are ultimately being forced toto implement other significant changes to current practices, rapidly transition to alternatives strategies for crops cur-including integration of new fumigant distribution and soil rently dependent upon methyl bromide, particularly wheninjection technologies, and new tillage and irrigation prac- product pricing has finally reached the $6.75 per poundtices to enhance the performance of alternatives and reduce mark and lower cost alternative strategies are needed afterpotential fumigant emissions from treated fields. With fruit pricing volatilities in the marketplace.Phase 2 labels and completion of the formal EPA fumigantreregistration process (spring 2012), all of the currently Clearly the time has arrived to document and describeregistered fumigant alternatives will have new restrictions a process for an orderly transition and implementation ofwhich will further restrict or limit their use (i.e., potential the alternatives. Many different timelines and acreageneeds for reduced rates and acreages treated per day and commitments to alternatives can be envisioned. A seamlessexpanded buffer zones. The new regulatory criteria for transition would commit new acreage to alternatives at afumigant use are designed to strongly encourage emis- rate equal to or greater than the rate that methyl bromidesion reduction strategies which include high barrier (more annually decreases in supply. Figure 1 depicts a timelinegas impermeable) plastic mulches to reduce overall field for orderly transition to alternatives as an inverse functionapplication rates and soil emissions of fumigant gases. of CUE approved levels of new methyl bromide produc-Grower transition to these new IPM methods (dashed blue tion. This projected transition timeline would indicate aline Figure 1) have been largely and only recently driven need for Florida growers to commit as much as 40% ofby limited methyl bromide supply and formulation avail- their acreage to alternatives by the end of calendar yearability, a significantly lower cost structure for combina- 2006, and to 70% and 95% by the end of 2007 and 2010,tions of chemical alternative strategies compared to that of respectively. In reality, this long term incremental approachmethyl bromide, and by many other field, pest, soil, crop, has not occurred, and only recently have growers transi-and economic considerations. The primary objective for tioned to broader use of the alternatives. The dashed lineany methyl bromide transition strategy has been to manage of Figure 1 represents what appears to be the more realisticadoption of alternatives over time, to minimize changes to and accurate scenario in which expedited grower transi-the crop production system, and define and remove perfor- tion to methyl alternatives is predominately driven by onlymance inconsistency of alternatives. lingering grower preference for methyl bromide, higher per pound pricing, and reduced availability of methyl bromide Imperatives for Transition in a desirable formulation within the marketplace (i.e., As Figure 1 illustrates, with each new year the amount 67/33).of methyl bromide new production approved for CUEs isgenerally less than the amount of methyl bromide approved Alternative Fumigant Chemicalsthe previous year. Up until 2009, it was widely believed Since 1993, many different alternative soil fumigantsthat these reductions in new production had not signifi- have been evaluated in field trials to characterize pest con-cantly impacted methyl bromide availability to Florida trol efficacy and crop yield response (Table 1). The resultsgrowers because of the buffering capacity of the previ- of these research trials have provided basis for overallously produced, existing supplies. Late in 2008 it became generalization of pesticidal activity for each of the alterna-apparent that the distribution of those available stocks tive fumigant chemicals. As a standard for comparison,resulted in shortages of methyl bromide in the regional this research has repeatedly demonstrated methyl bromidedistribution system. As existing commercial stocks were to be very effective against a wide range of soilbornedepleted and international approval for production of new pests including nematodes, diseases, and weeds. Methylproduct decreases, severe shortages in methyl bromide iodide, a recent entry to registered fumigants in Florida,supply were beginning to be observed in late fall 2006 and has shown similar broadspectrum pest control activity2008 and have continued to amplify with each cropping as that of methyl bromide. Chloropicrin has proved veryseason since. Approved CUE levels for new production effective against diseases but seldom nematodes or weeds.and consumption for 2012 are currently projected at 3.0% Telone (1, 3-dichloropropene) is an excellent nematicideof the 1991 baseline level, a significant reduction from the but generally performs poorly against weeds and diseases.previous year of 7.25%. With Florida CUE vegetable acre- Bacterial pathogens have not been satisfactorily controlledage relatively unchanged, there are currently inadequate by any of the fumigants. Metam sodium and metam potas-supplies to meet former demands and extensiveness of use. sium can provide good control of weeds when placed prop-
Chapter 6: Alternatives to Methyl Bromide Soil Fumigation for Florida Vegetable Production Page 49erly in the bed, however research to evaluate modification has affected field research priority involves new, lessof rate, placement, and improved application technology demanding buffer zone distance requirement to surroundhave not resolved all problems of inconsistent pest control. fumigant treated fields. As a result, field research focus hasDimethyl disulfide (DMDS), the newest entry to registered shifted back towards evaluations of in-bed shank appliedfumigants in Florida, has demonstrated good to excellent fumigant treatment.control of nematodes, disease, and weeds when coappliedwith chloropicrin. To ensure deeper placement, Telone II can be injected to flat soil prior to any soil mounding or bed forming opera- Much of the current field research continues to focus tion (PreBed) to a depth of at least 12 inches below theon evaluations of chloropicrin co-applied with additional final bed top with the second fumigation pass applyingfumigants. In this co-application approach, chloropicrin the chloropicrin in the bed at 8 to 9 inches below the finalhas clearly been shown to be an integral, foundation com- bed top. In-row or prebed applications of Pic-Chlor 60ponent of any alternative chemical approach to replace or Telone C35, or more recently with drip applications ofmethyl bromide. Of the chloropicrin combinations, includ- Telone Inline or Pic-Clor 60 EC continue to be field evalu-ing Pic-Clor 60, Telone C-35, a combination of 1,3-dichlo- ated for pest control efficacy.ropropene and 35% chloropicrin, has been the most exten-sively evaluated in Florida field trials since 1994. DMDS Research conducted in Florida and areas of the south-in combination with chloropicrin (21%) has also been east appear to support the general conclusion that reason-extensively studied in west central and south Florida field ably consistent soilborne pest and disease control can betrials. Over the past few years, anticipated label changes obtained with in-row or prebed applications of Telone C35regarding personal protective equipment (PPE) and buffer (35 gal/A) or Telone II, applied at 12 gallons per treatedzone requirement has focused Florida field research activi- acre followed by chloropicrin applied in the bed at 150ties on evaluations of application methods which minimize pounds per treated acre. In combination with Telone II,grower impacts, such as drip fumigation and prebed shank Telone C35 or Chloropicrin, use of a high barrier or virtu-applications. With the new fumigant labels of January 1, ally impermeable mulch film (VIF) will generally improve2011, many new, less demanding, requirements for per- fumigant performance and reduce soil gas emissions. Aftersonal protective equipment are now in effect. For example, EPA completion of fumigant reregistration (expected springfull face respirator must only be worn if a handler in the 2012), EPA will only recognize use of specific high barrierfield complains of sensory irritation and the certified appli- or true VIF mulch films where film permeabilities (masscator decides to remain in the field and to continue fumiga- transfer coefficients) to the different fumigant gases havetion. Other changes in new fumigant label language which been measured and meet EPA approved emission reductions Table 1. Generalized Summary of maximum use rate and relative effectiveness of various soil fumigant alternatives to methyl bromide for nematode, soilborne disease, and weed control in Florida. Relative Pesticidal ActivityFUMIGANT CHEMICAL1 Maximum Use Rate Nematode Disease Weed1) Methyl bromide 50/50 350 lb Good to Excellent Excellent Fair to Excellent2) Chloropicrin2 300 lb None to Poor Excellent Poor3) Methyl iodide 350 lb Good to Excellent Good to Excellent Good to Excellent4) Metam sodium 75 gal Erratic Erratic Erratic5) Telone II 18 gal Good to Excellent None to Poor Poor6) Telone C17 26 gal Good to Excellent Good Poor7) Telone C35 35 gal Good to Excellent Good to Excellent Poor to Fair8) Pic-Clor 60 300 lb Good to Excellent Good to Excellent Poor to Fair9) Metam potassium 60 gal Erratic Erratic Erratic (Kpam)10. Dimethyl disulfide2 60 gal Good to Excellent Good to Excellent Poor to Excellent1 urrenly completing Phase 2 EPA and State of Florida Fumigant Reregistration review with potential changes to maximum application rate, new fumigant training certifications, C personal protective equipment, buffer zone, mandatory good application practices, and other new restrictions and requirements.2 road spectrum pest control achieved when coapplied with chloropicrin (21% wt/wt). Provides excellent control of nutsedge but poor to fair control of annual grasses and B requires the use of a herbicide for adequate control.
Page 50 Vegetable Production Handbook Table 2. Recommended alternative fumigant and herbicide treatment regime to that of methyl bromide for Florida1 tomato, pepper, egg- plant, and strawberry crops. All rates expressed per treated acre. To achieve maximum weed control an application of Metam sodium (Vapam) at 75 gal/A or Metam potassium (KPam) at 60 gal/A should be included to all recommended products using a mini coulter appli- cator or through a drip application using double drip tapes.CROP Treatment Application Procedure Herbicide Rate (lb a.i./A) Telone C35 In-Row or Pre-Bed2, under LDPE, High Barrier or VIF Mulch 35 gal/A Film3; applied 3-5 weeks before transplanting Telone II Telone Pre-Bed2, Chloropicrin In-bed under High Barrier or VIF Mulch Film3; applied 3-5 weeks before transplanting Napropamide (2lb) 12 gal/A S-metolachlor (0.95 lb)Tomato Chloropicrin Postemergent 150 lb/A Halosulfuron (0.036 lb) Pic-Clor 60 Pic-Clor 60 In-Row or Pre-Bed2 under High Barrier or VIF 250-300 lb/A Mulch Film3; applied 3-5 weeks before transplanting 4DMDS (79%)+ In-Row or Pre-Bed2, under High Barrier or VIF Mulch Film3; PIC(21%) applied 3-5 weeks before transplanting 60 gal/A Telone C35 In-Row or Pre-Bed2, under LDPE, High Barrier or VIF Mulch 35 gal/A Film3; applied 3-5 weeks before transplanting Telone II Telone Pre-Bed2, Chloropicrin In-bed under High Barrier or 12 gal/A VIF Mulch Film3; applied 3-5 weeks before transplantingPepper Napropamide (2 lb) Chloropicrin S-metolachlor (0.71 lb, 3rd party label 150 lb/A obtained through FFVA) Pic-Clor 60 Pic-Clor 60 InRow orPre-Bed2 under High Barrier or VIF 250-300 lb/A Mulch Film3; applied 3-5 weeks before transplanting 4DMDS(79%) + In-Row or Pre-Bed2, under High Barrier or VIF Mulch Film3; PIC(21%) applied 3-5 weeks before transplanting 60 gal/A Telone C35 In-Row or Pre-Bed2, under LDPE, High Barrier or VIF Mulch 35 gal/A Film3; applied 3-5 weeks before transplanting Telone II Telone Pre-Bed2, Chloropicrin In-bed under High Barrier or 12 gal/A VIF Mulch Film3; 3-5 weeks before transplantingEggplant Chloropicrin 150 lb/A Pic-Clor 60 Pic-Clor 60 In-Row or Pre-Bed2 under High Barrier or VIF 250-300 lb/A Mulch Film3; applied 3-5 weeks before transplanting 4DMDS (79%)+ In-Row or Pre-Bed2, under High Barrier or VIF Mulch Film3; PIC(21%) applied 3-5 weeks before transplanting 60 gal/A Telone C35 In-Row or Pre-Bed2, under LDPE, High Barrier or VIF Mulch Napropamide (4 lb)Strawberry 35 gal/A Film3; 4-5 weeks before transplanting Oxyfluorfen (0.5 lb)1 Crop recommendations for Pic-Clor 60, Telone II or Telone C35 do not apply to the Homestead, Dade County production region of south Florida where soil types and water tables currently prohibit product use.2 Inject Telone II, Telone C35, or Pic-Clor 60 to flat soil prior to any soil mounding or bed operation (PreBed) to a depth of at least 12 inches below the final bed top.3 n combination with fumigant, use of an EPA approved high barrier or virtually impermeable (VIF) or totally impermeable (TIF) mulch film. With use of the mulch, fumigant rates I can be reduced 25 to 40% from maximum pesticide labeled application rate.4 MDS (dimethyl disulfide) (79%) co-formulated with 21% chloropicrin. Its use has not been broadly tested in Florida but has proved very effective against nematode and D disease, and for many weeds. Provides excellent control of nutsedge but only poor to fair control of annual grasses and requires the use of a separately applied herbicide for adequate control.
Chapter 6: Alternatives to Methyl Bromide Soil Fumigation for Florida Vegetable Production Page 51to qualify for buffer zone reducing credits. With use of the with metam sodium or potassium applied through a seriesmore impermeable plastic SIF or VIF mulches, fumigant of minicoulters to the established plant bed just beforerates can be reduced 25 to 40% from maximum labeled installation of the plastic mulch. Good control of yellowapplication rates. Due to use restrictions for all Telone and purple nutsedge has also been recently demonstrated inproducts in Dade County, either metam sodium or metam limited tomato trials with Eptam (S-ethyl dipropylthiocar-potassium at 75 and 60 gallons per acre respectively, in bamate, 3rd party label obtained through FFVA), howevercombination with shank injections of chloropicrin (150 these applications are only safe when used under LDPEpounds per treated acre) and appropriate herbicide(s) are (conventional) mulch.currently defined as the best alternatives to methyl bromide.With Florida registration on May 13, 2011, use of dimethyldisulfide (Paladin), in combination with chloropicrin and HIGH BARRIER / VIRTUALLY IMPERMEABLEmetam sodium or potassium is also expected to provide abasis for statewide grower trialing of yet another effective PLASTIC MULCH FILMS (VIF)alternative chemical approach to replace methyl bromide. Since the early 1960’s, low density polyethylene mulch Given the general lack of herbicidal activity associated film (LDPE) has been used as an integral component of thewith the alternative fumigants, weed control is usually raised bed, methyl bromide soil fumigation, seep irrigatedassigned the highest pest management priority for most vegetable production system of Florida. In this system, themethyl bromide alternative chemical systems. Regardless mulch is important because it confers effective nonchemi-of crop, separate application of one or more herbicides is cal weed control and minimizes evaporative losses ofa requirement for effective weed control with any methyl water from soil and nutrient leaching due to frequent rain-bromide chemical alternative system. In general, weed fall. Use of LDPE is also a federal label requirement forcontrol with these alternative fumigants (including Vapam use of methyl bromide, where it must be installed imme-or KPam) plus herbicides is reported as good or better diately after fumigant injection into soil. Unfortunately, asthan that of methyl bromide. There are however numerous much as 30 to 80% of the methyl bromide applied to soil isexamples of less than ideal herbicide performance in which estimated to escape the plant bed through the LDPE mulchvarious grasses and broadleaf weeds were not effectively cover. It is obvious that the barrier properties of LDPE tocontrolled. The problems incurred usually demonstrate the fumigant gases is quite poor, particularly given the 0.7 toimportance of soil conditions, incorporation method, and 1.2 mil thick films typically used in Florida agriculture.improper rate calibration for good weed control, as well as In general, the wide range in outgassing losses of methylfor inducing significant phytotoxic effects and cause for bromide is not just due to the permeability of the plasticresultant yield losses. mulch cover, but to the range in cultural practices and environmental conditions (hot, dry) occurring at the time Herbicide Partners of soil fumigation. In addition to Telone II plus chloropicrin, Telone C35,or PicClor 60, additional applications of appropriate The permeability (the ability to pass through) of plasticherbicides will be necessary to provide weed control for mulch to a fumigant gas is directly related to the thickness,any CUE crop (Table 2). For tomato, follow the fumi- density, and chemical composition of the plastic sheet.gant prebed application of Telone C35 or Telone II and Regardless of composition, thicker mulches are generallyChloropicrin with a tank mix of napropamide (2 pounds less permeable to methyl bromide than are thin mulches.a.i.) and s-metolachlor (0.95 pounds a.i.) per treated acre In most cases, practical and cost efficiency considerationsapplied to the top of the raised bed at plastic laying for prevent the use of thicker LDPE mulches for enhancedweed control. An additional application of halosulfuron containment of methyl bromide soil gases. There are how-(0.024 pounds a.i.) as a post-emergent, directed spray for ever other, more impervious, plastic mulches commerciallynutsedge control may be necessary. For strawberry, the available which can provide a much better diffusion barrierfumigant application of Telone C35 is supplemented by a to methyl bromide and other soil fumigants. These newherbicide tank mix of oxyfluorfen (0.5 pounds a.i.) plus low permeability films, and the classification scheme tonapropamide (4 pounds a.i.) per treated acre, to the raised describe them, include totally impermeable films (TIF),bed surface at plastic laying. (Note: A minimum 30-day virtually impermeable films (VIF), and semi-impermeableinterval is required before transplanting when using oxy- films (SIF) which include the metalized films. These films,fluorfen.) In pepper, a herbicide tank mix of napropamide compared to standard polyethylene (PE) films, can reduce(2 pounds a.i.) and s-metolachlor (0.71 pounds a.i., 3rd fumigant emissions to the atmosphere and via improvedparty label obtained through FFVA) per treated acre is containment in soil and cumulative time x concentrationapplied after the Telone II Pre-Bed and Chloropicrin injec- products, improve fumigant performance even at reducedtion to the raised bed at plastic laying for weed control. rates of fumigant application.Recent research on soil application technologies in Floridaand Georgia have demonstrated improved nutsedge control
Page 52 Vegetable Production Handbook As indicated, significant barrier to fumigant outgas- sides). The mass transfer coefficient characterizes the equi-sing has been achieved with VIF and TIF mulches. VIF librium condition, and thus provides an intrinsic signaturemulches, the most widely studied, are typically manufac- measure of the permeability of a film to a chemical whichtured as multi-layer films composed of barrier polymers is not dependent on the chosen concentration gradient.such as ethylene vinyl alcohol (EVOH) or polyamide Because the new method produces such a sensitive and(nylon) sandwiched between other polymer layers (typi- reproducible measure of film permeability between labora-cally LDPE) that keep the barrier polymers from swelling. tories, it is now being widely adopted as the new yardstickCompared to LDPE mulches, certain VIF films are over for comparing fumigant permeabilities among the high bar-20,000 times less permeable to methyl bromide and other rier plastic mulches.fumigant compounds. The permeability of these mulchesis however subject to variation induced by physical and During the past decade, many small plot and large scalesuboptimal environmental condition. For example, VIF field trials have been conducted in Florida to evaluate thehas been shown to have extremely low permeability under use of high barrier SIF, VIF, and TIF mulch films to reducelaboratory conditions (before tarping), but its permeability methyl bromide field application rates, reduce soil emis-can change significantly under field conditions after tarp- sions, and to compare crop yield and pest control efficacy.ing. After laying the plastic in the field, some SIF and VIF In general, the results of these trials have indicated no sig-mulch films may be as much as 2 to 3 times more perme- nificant loss of pest control efficacy or of crop yield whenable to a given fumigant gas than they were under labora- applications rates of methyl bromide were reduced as muchtory condition. This is thought to be due to a breakdown as 25 to 50% when reduced rates were accompanied by thein the VIF properties under field conditions caused by the use of a TIF, VIF or high barrier SIF mulch. In a numberstretching and cracking of the middle, low permeability of trials, attempts to further reduce use rates by more thanlayer during tarping. 50% resulted in a loss of pest control efficacy and crop growth performance. Opportunities for reducing field Quantitatively, the permeability of LDPE, TIF, VIF and application rates of other fumigants without compromisingother SIF mulch films to a fumigant gas were formerly pest control efficacy or crop yield have also been demon-expressed as the amount of a fumigant (grams) passing strated with methyl iodide.through the mulch cover per unit time (hr) and per unit sur-face area. VIF mulches were first developed and mandated More recently, field research has demonstrated thatfor use in Europe, where to be labeled VIF, film manu- certain metalized mulches (Canslit) had significant bar-facturers were forced to comply with a standard testing rier, VIF-type qualities. The thin coating of aluminum wasprotocol (NFT 54-105), established by the French Ministry demonstrated to retain higher methyl bromide concentra-of Agriculture. The French standard specifies that in order tions in soil for longer periods of time, and thus providedfor a film to be classified as VIF, its permeability to methyl effective weed control (ie., nutsedge), with reduced rates ofbromide could not exceed 0.20 g/m2/hr. Alternative stan- methyl bromide comparable to that of true VIF mulch film.dards for expressing permeability, such as the mass transfer The utility of the metalized mulch for allowing reducedcoefficient, are now being adopted for use in defining high fumigant application rate has also been demonstrated inbarrier and gas impermeable plastic mulches. other states of the southeast. The more efficient contain- ment of gases below the barrier mulch has also resulted in This new reference standard, the Mass Transfer cases of crop phytotoxicity. To use the high barrier mulchCoefficient (h) of fumigant compounds across agricultural technology, plantings may have to be delayed to insure soilfilms, is a measure of the resistance to diffusion which, residues have dissipated and plant injury will not occur.unlike the French standard, is a property of the film / A monitoring program using colormetric detector tubeschemical combination and is independent of the concen- (GasTek, Kitagawa, Sensidyne) or VOC meters to assesstration gradient across the film. The French method com- residual fumigant gases in soil should be considered beforeputes permeability based on fumigant flux or fluctuation, a commitment to planting is made.so many grams of fumigant per unit surface area per unittime. As a measure of permeability, the French standard Noteworthy problems have been encountered withis thus dependent (and will necessarily change) upon the some VIF mulches. In some strawberry trials, where tallerconcentration gradient or concentration difference occur- yet narrower beds are used, the slick, nonembossed VIFring on each side of the film. In the French method, the mulches could not be installed without the need for signifi-concentration difference between sides is seldom the same cant hand labor. Since the VIF plastics were not embossed,(not standardized), and thus cannot be compared between they demonstrated a tendency to slip from under the rearindependent laboratory based estimates. The Mass Transfer press wheels during installation causing significant reduc-Coefficient method however, uses static sealed cells; where tions in tractor speeds and frequent stoppages in the plastica fumigant gas is introduced (spiked) to one side of the laying operation. The problem with use of nonembossedfilm and the concentrations on both sides of the film are does not appear to be as severe in tomato or pepper wherethen monitored until an equilibrium is reach (same on both the raised plant beds are wider and not as tall as that of
Chapter 6: Alternatives to Methyl Bromide Soil Fumigation for Florida Vegetable Production Page 53strawberry. Since these VIF mulch have no stretch capa- use rate, the bigger the buffer zone from residential prop-bility, adding 2 inches of width to the roll (if possible) erty line or occupied structures required). Any new bufferhas in many cases reduced, not eliminated, problems of zone and use rate restriction will surely mandate a morefield installation in strawberry by providing more plastic intensive, overall re-evaluation of alternatives and reducedat the tuck in the row middle. With the appearance of rate application technologies, including use of high barriermany newly formulated VIF products, including the new SIF, VIF, and TIF type mulches to take advantage of bufferembossed high barrier mulches, the previous problems of zone reducing credits, assure pest control efficacy and cropinstallation may be largely resolved. response consistency. As indicated previously, EPA will only recognize use of specific high barrier SIF, TIF, or true From a practical standpoint, grower adoption of VIF VIF mulch films where film permeabilities (mass transferor other high-barrier films, coupled with reduced soil coefficients) to the different fumigant gases have beenfumigant application rate will require continued in-field measured and meet EPA approved emission reductions toevaluations, with continued refinement of field installa- qualify for buffer zone reducing credits.tion application technologies and evaluations of reducedrate pest control efficacy. Increased use of TIF and VIFmulch films must also consider changes in production cost REDUCED RATE APPLICATION TECHNOLOGIESand benefits to productivity. Today, over a dozen differ-ent manufacturers or product lines can be identified which Currently, soil injection equipment for methyl bromideclaim high barrier, VIF or TIF status. Many of these new is designed to dispense as much as 15 to 20 gallons of ahigh barriers, VIF, and TIF products are now being pro- liquid fumigant compound through armored lines fromduced in the U.S. and Canada, while others may originate the gas cylinder, to the flow meter and rear manifold andfrom international manufacturers. Any growers acquiring then through each of three chisel per bed. The system isfilms from overseas manufacturers should be encouraged designed and calibrated to do this while moving at 3½ toto order necessary products well in advance of the time of 5 mph, uniformly dispensing multiple liquid streams ofneed in the field. fumigant within 7260 to 10, 890 linear feet of row per acre. With such high rates, the flow lines are full, with Probably the single most important reason for using a liquids moving as continuous streams without in-line voidsVIF or other high barrier SIF plastic mulch involves the or bubbles. At reduced rates of application, such as thoserising cost and scarcity of methyl bromide with each new demanded for use with high barrier or VIF film, the situa-CUE approval. There are other, equally important reasons tion may be vastly different.for adopting high barrier, VIF mulch technologies. Aftera long EPA fumigant reregistration process, new fumigant Methyl bromide is a colorless, odorless, liquid underlabels appeared on product containers of methyl bromide, certain conditions of pressure and temperature. At tem-chloropicrin, metam sodium (Vapam) and metam potas- peratures below the boiling point of 38° F, or within thesium (Kpam) on January 1, 2011. The new fumigant labels confines of a pressurized cylinder, methyl bromide existshave clearly enumerated a number of newly mandated as a liquid. At temperatures typical of field application inrules, restrictions, and regulatory changes which must be Florida, methyl bromides rapidly volatilizes to a gas oncesatisfied prior to use of all of the alternative fumigants. For release from the pressurized cylinder into the ambient pres-example, if a respirator is required to be worn by handlers sure of air or soil. With such a high vapor pressure (1420in the application block, then OSHA approved pesticide mm Hg), methyl bromide can even exist as bubbles of gassafety training, medical certification, and respirator fit test- within the distribution lines if metered flow rates are lowing will be required by the new labels. The new labels will and do exceed the total capacity of the delivery tubingalso require certified applicators to complete and archive and manifold system. With reduced flow and presence offumigant management plans (FMP) and post application bubbles within lines, a significant loss of back pressuresummaries for each application block in which a fumiga- occurs at the chisel orifices. The dramatic fall in back-tion occurs. Effective with a second round of new labels pressure with reduced rate prevents accurate and uniformcoming sometime during spring 2012, these new label flow of the fumigant between chisels. This occurs at thechanges will include requirements for certified applicators point where total internal volume (flow capacity) of 9to acquire additional product use and stewardship training chisel tubes, typically ¼ inch in diameter, exceeds the flowevery 1 to 3 years depending upon the fumigants being capacity of a ¾ armored delivery hose from the flow meter.used in the field, as well as expanded buffer zones between When the outflow potential is greater than inflow thenagriculturally treated lands and urban residential property you have a significant loss of pressure, and without backand or occupied structures. Buffer zone requirements, areas pressure the system becomes one of gravity flow. Withextending outward from the treated field where fumigants the existing on-farm systems, accuracy cannot be achievedcannot be applied, will be calculated and dependent upon at such low volumes, and without significant back pres-methods of fumigant application, the number of acres treat- sure. To resolve the back pressure problem, it is extremelyed per day, and field application rate (the higher the field important to reduce total line volume and/or diameter of
Page 54 Vegetable Production Handbookthe delivery tubes from the manifold to the chisels so as to the transition is not likely to be uneventful or withoutguarantee adequate back pressure at the point of fumigant problems. In many cases, problems have been reducedrelease. With a high barrier mulch, reducing the field appli- after comprehensive review and a complete analysis of thecation rate of a fumigant results in a greatly reduce rate of entire production system. The transition is not likely to beliquid flow. Some chisels are so reduced in flow that accu- easy or seamless. If the transition plans are well designedracy and uniformity of application along and between the and implemented effectively, problems are likely to be few.rows was compromised along with pest control efficacy. Unavoidably however, some factors that affect the success or failure of the various tactics, such as the environment, As indicated previously, use of VIF or high barrier may not be completely manageable or resolvable. Forplastic mulch films will be a required component of any example, seasonal differences in temperature and rainfallmethyl bromide transition strategy. Use of these more gas patterns can adversely effect fumigant dissipation fromretentive mulches will however, require changes in field soil, and herbicide efficacy and thus reduce the value ofapplication and soil injection equipment to insure accurate the alternative by causing treatment inconsistency. Growersand uniform dispensing of such low fumigant application can also cause significant response variability due torates (5 to 10 gallons per acre). These required changes inappropriate land preparation or substandard applicationinclude smaller delivery tubing size (1/8 to 1/16 inch procedures. Another newly emerging concern is the riskdiameter), installation of sight gauges to monitor flow created by the differential plant-back restrictions of someuniformity among chisel streams, and installation of a low of the newly registered herbicide compounds that have topressure gauge upstream of the flow divider to monitor be added for weed control with the alternative fumigants.overall back pressure (at least 15 psi) at the flow divider The impacts on the ability to double crop, as well as poten-(Table 3). For additional, more comprehensive information, tial direct yield reduction as a result of carryover from rowreaders are advised to review “Application Considerations middle or previous crop applications, are also of concern.for Successful Use of VIF and Metalized Mulches withReduced Fumigant Rates in Tomato”. Appendix ; or Effective transition planning can only be achievedhttp://edis.ifas.ufl.edu/HS270) through a collaborative effort involving the grower and his field staff, commodity organization involvement, assisted by university research and extension personnel. Working together, the team should craft a realistic transition plan TRANSITION RISKS that addresses many of the production concerns and incon- Transition refers to an incremental change from current sistencies. The transition plan would also surely highlightstatus. Defined in this way, the transition from methyl bro- the imperative that Florida fruit and vegetable growersmide fumigation is the change from a 40-year-old system actively complete the transition, to increased reliance uponof being totally reliant on methyl bromide to a new multi- the alternative fumigants as a percentage of their totaltactic pest control and crop production system. Clearly, farmed acreage. Table 3. Summary of recommended fumigant injection equipment modifications required for use of high barrier / VIF mulch and reduced rate applications of soil fumigants.Replace tubing from manifold to chisels with smaller diameter poly tubing to compensate for the new reduced flow capacity requirement and toincrease line back pressure needed to insure accurate, uniform flow among all chisel streams.To the manifold - flow divider, install individual sight gauges to observe uniformity of fumigant liquid flow to each chisel outlet.Install a low pressure gauge (0-30 psi) immediately upstream of the manifold or flow divider to insure at least 15 psi of backpressure.Insure that the flow meter registers a minimum of 10% flow.
Chapter 7. 2012-2013Cole Crop Production in FloridaS.M. Olson, P.J. Dittmar, G.E. Vallad, S.E. Webb and S.A. Smith BOTANY SEEDING AND PLANTING Nomenclature Family - Brassicaceae (Cruciferae) Seeding and planting information for cole crop produc- Broccoli - Brassica oleraceae Italica group tion in Florida is given in Table 3. Cabbage - rassica oleraceae Capitata group B Cauliflower - rassica oleraceae Botrytis group B Collards - Brassica oleraceae Acephala group FERTILIZER AND LIME Kale - Brassica oleraceae Acephala group Mustard - Brassica juncea Soil test and fertilizer recommendations for cole crops Turnip - Brassica rapa Rapifera group grown on mineral soil are shown in Table 4. Origin For unmulched crops planted in single rows or beds, It is believed that all of the crops within B. oleraceae broadcast all P2O5, micronutrients, and 25 to 50% of N andevolved from a wild cabbage-like plant that was native to K2O before planting. Banding these fertilizers at plantingthe British Isles and to the Mediterranean area of Europe. might improve fertilizer efficiency. Sidedress remaining N and K2O at 6 to 8-leaf stage. Related Species Other vegetables in the Brassicaceae family are horse- For unmulched leafy cole crops planted in multi-rowradish, rutabaga, Brussels sprouts, kohlrabi, Chinese cab- beds, broadcast P2O5, micronutrients, and 25 to 50% of thebage, radish, and watercress. Many ornamental plants and N and K2O in the bed area. Topdress or band remaining Noil-bearing plants also are included in this family. and K2O when plants are 4 to 6 inches tall. Apply supple- mental N and K2O (as above) after leaching rain. VARIETIES Table 2. Broccoli, cauliflower, collard, kale, mustard, and turnip varieties grown in Florida. Florida cabbage varieties are shown in Table 1. Othercole crop varieties are shown in Table 2. Broccoli: Kale: Arcadia (H) Blue Ridge (H) Marathon (H) Vates Major (H) Mustard: Packman (H) Florida Broad Leaf Table 1. Some cabbage varieties grown in Florida. Patriot (H) Green Wave Green Red Pirate (H) Red Giant Atlantis (H) Green Cup (H) Cardinal (H) Cauliflower: Southern Giant Curled Augusta (H) Isalco (H) Red Dynasty (H) Majestic (H) Tendergreen White Passion (H) Turnip: Blue Dynasty (H) Matsuma (H) Red Success (H) Snow Crown (H) Just Right (H) Bravo (H) Pruktor (H) Red Rookie (H) Collards: Southern Green Cheers (H) Ramada (H) Blue Max (H) Purple Top Ducati (H) Rio Verde (H) Bull Dog (H) Royal Crown (H) Emblem (H) Royal Vantage (H) Flash (H) White Knight (H) Gideon (H) Solid Blue 790 (H) Georgia Turnip Greens: Gloria (H) Tropicana (H) Top Bunch (H) Seven Top Savoy Top Pick (H) Savoy Ace (H) Vates H = hybrid. H = hybrid. Page 55
Page 56 Vegetable Production Handbook Table 3. Seeding and planting information for cole crops in Florida. Planting dates Broccoli1 Brussels sprouts Cabbage1 Cauliflower 1 North Florida Aug - Feb Aug - Feb Aug - Feb Aug - Feb Central Florida Sept - Feb Sept - Feb Sept - Feb Sept - Feb South Florida Oct - Jan Oct - Jan Sept - Jan Sept - Jan Seeding information Distance between rows (in) 24 - 40 24 - 40 24 - 40 24 - 40 Distance between plants (in) 10 - 15 18 - 24 9 - 16 12 - 18 Seeding depth (in) 0.25 - 0.5 0.25 - 0.5 0.25 - 0.5 0.25 - 0.5 Seeding per acre for field (lb) 1-2 1-2 1-2 1-2 Seeding per acre for transplant (lb) 1.25 - 1.5 1.25 - 1.5 1 1.25 - 1.5 Days to maturity from seed 75 - 90 90 - 120 85 - 110 75 - 90 Days to maturity from transplant 50 - 70 70 - 90 70 - 90 50 - 70 Plant populations2 (per acre) 26,136 15,520 29,403 29,040 Planting dates Collards Kale Mustard Turnip North Florida Aug - Feb Aug - Feb Aug - Feb Aug - Feb Central Florida Sept - Feb Sept - Feb Sept - Feb Sept - Feb South Florida Sept - Jan Sept - Jan Sept - Jan Sept - Jan Seeding information Distance between rows (in) 24 - 36 18 - 24 12 - 36 12 - 36 Distance between plants (in) 12 - 24 8 - 12 5 - 10 2-6 Seeding depth (in) 0.25 - 0.5 0.25 - 0.5 0.25 - 0.5 0.25 - 0.5 Seeding per acre for field (lb) 2-4 2-4 3-5 2-3 Seeding per acre for transplant (lb) 1.25 - 1.5 N/A3 N/A3 N/A3 Days to maturity from seed 70 - 90 50 - 70 40 - 50 40 - 60 Days to maturity from transplant 50 - 70 — — — Plant populations2 (per acre) 21,780 43,560 116,160 261,360 1 Can be seeded in double rows per bed: 15 - 24 in between rows, 10 - 12 in within rows on 40 to 60-inch bed centers. 2 Populations based on closest between and within row spacing, 3 Generally direct seeded. For mulched crops with subsurface irrigation, incorpo- For drip-irrigated crops, (broccoli, cauliflower, cabbage,rate all P2O5, micronutrients, and 20 to 25% of N and K2O collards) apply all P2O5, micronutrients, and up to 20 toin the bed. Apply remaining N and K2O in a single groove 25% of N and K2O in the bed at planting. Apply remain-(for twin-row) in bed center about 2 to 3 inches deep ing N and K2O through tube using schedules presented inbefore mulching. Supplemental N and K2O can be injected Table 6a and 6b.through mulch with a liquid fertilizer injection wheel. For leafy cole crops other than those listed here, follow For mulched crops with overhead sprinkler irrigation, recommendations for mustard.incorporate all fertilizer in bed before mulching. Bed overfertilized soil with unfertilized soil so that fertilized soilwill be deep enough (3 to 4 inches) to remain moist. PLANT TISSUE ANALYSIS Plant tissue analysis for cole crops is listed in Table 7. For Histosols, all P2O5, K2O, and micronutrients canbe broadcast just before planting, although banding P2O5at planting might increase P efficiency. Some N might be PETIOLE SAP TESTINGneeded for crops started under cool, winter conditions. A Fresh sap can be pressed from leaf petioles and ana-total of 40 to 50 lb N per acre might be needed at planting lyzed for nitrogen and potassium concentrations. Resultsor as a sidedress early in the season (see Table 5). can be used to make adjustments in the fertilization pro- gram. Sufficiency ranges for sap testing broccoli and col- lards are presented in Table 8.
Chapter 7: Cole Crop Production in Florida Page 57 Table 4. Soil test results and fertilizer recommendations for cole crops on mineral soils.1 VL L M H VH VL L M H VH P2O5 K2O Target pH N lb/A (lb/A/crop season) Broccoli/Cauliflower/Brussels sprouts 6.5 175 150 120 100 0 0 150 120 100 0 0 Cabbage/Collards/Chinese cabbage 6.5 175 150 120 100 0 0 150 120 100 0 0 Kale/Turnip/Mustard 6.5 120 150 120 100 0 0 150 120 100 0 0 1 See Chapter 2 section on supplemental fertilizer application and best management practices, pg 11. Table 5. Soil test and fertilizer recommendations for cole crops grown on Histosols, with target pH 6.0 and N rate= 0 lb/A. P and K index and fertilizer rate Crop P index 3 6 9 12 15 18 Broccoli, Cauliflower P2O5 (lb/A) 200 140 80 20 0 0 Cabbage P2O5 (lb/A) 200 140 80 20 0 0 Chinese cabbage P2O5 (lb/A) 280 220 160 100 40 0 K index 50 80 110 140 170 200 Broccoli, Cauliflower K2O (lb/A) 200 140 80 20 0 0 Cabbage K2O (lb/A) 200 140 80 20 0 0 Chinese cabbage K2O (lb/A) 200 140 80 20 0 0 IRRIGATION INSECT MANAGEMENT Slight variations exist in the water requirements of The key pest of cole crops in Florida is the diamond-members of the cole crop family (see Chapter 3, Principles back moth. Resistance to insecticides, particularly to pyre-and Practices of Irrigation Management for Vegetables, throids, is very common. If diamondback moth larvae areTables 4-6). Water use rates may approach ETo (see present, growers should avoid pyrethroids and use BacillusChapter 3, Table 3) during the rapid growth and develop- thuringiensis products (both aizawa and kurstaki strains) asment period, decreasing to 85% of that value during final their main insecticides and tank mix or alternate with spi-growth. Reductions in available water to the plants will nosad or emamectin benzoate. If cabbage looper is present,result in reduced growth and development of leaves and in addition to diamondback moth larvae, an application ofshoots. Winter season water use in south Florida may aver- methomyl may be necessary. Another choice is thiodicarbage 0.10 inches per day (2700 gal/A/day), while in north but this will be more damaging to beneficial insects thanFlorida, requirements may average 0.06 inches per day methomyl, which has a short residual effect. If diamond-(1600 gal/A/day), a 40% difference. Therefore, close atten- back moth is not present and cabbage looper is the maintion to local climatic conditions is necessary for proper pest, a pyrethroid would be effective. Tebufenozide willwater management and irrigation scheduling. also control cabbage looper but not diamondback moth larvae. WEED MANAGEMENT The insecticides currently approved for use on insects attacking cole crops are outlined in the following tables: Herbicides labeled for weed control in cole crops are Cole crops - Table 11listed in Table 9. Turnip - Table 12 DISEASE MANAGEMENT PRODUCTION COSTS Information on managing diseases of cole crops is given Example breakeven production costs for cabbage arein Table 10. given in Table 13.
Page 58 Vegetable Production Handbook Table 6a. Injection schedule for N and K for cole crops planted two rows per bed on 6-foot centers on soils very low in K. Total nutrients (lb/A)3 Crop development Injection (lb/A/day)1 Crop N K 2O Stage Weeks2 N K 2O Broccoli 175 150 1 1 2.0 1.75 Cauliflower 175 150 2 9 2.5 2.25 Cabbage 175 150 1 3 2.0 2.0 Collards 175 150 2 6 2.5 2.5 Chinese cabbage 175 150 3 2 2.0 2.0 1 ll nutrients injected. Actual amounts may be lower depending on amount of N and K O placed in the bed, the K soil test result, and the crop N requirement. A 2 2 tarting from date of seedling emergence or transplanting. First two weeks worth of injecting can be omitted if 25% of total N and K O was applied preplant. S 2 3 eeds and transplants may benefit from applications of a starter solution at a rate no greater than 10 to 15 lbs/acre for N and P O , and applied through the plant hole or near S 2 5 the seeds. Table 6b. upplemental fertilization recommendations for cole crops grown in Florida on sandy soils testing very low in S Mehlich-1 potassium (K20). Recommended-Supplemental fertilizationz Measured "low" plantProduction System Nutrient Leaching raint,u nutrient content x.w.u Extended harvest season x.uPlasticulture N n/a 1.5 to 2 lbs/A/day for 7 days y 1.5 to 2 lbs/A/day y,v K2O n/a 1.5 to 2 lbs/A/day for 7 days y 1.5 to 2 lbs/A/day y,vBare ground N 30 lbs/As 30 lbs/As 30 lbs/A v K2O 20 lbs/As 20 lbs/As 20 lbs/A vz A = 7,260 linear bed feet per acre (6-ft bed spacing); for soils testing "very low" in Mehlich 1 potassium (K O) 1 2y ertilizer injections may be done daily or weekly. Inject fertilizer at the end of the irrigation event and allow enough time for proper flushing afterwards. Fx lant nutritional status may be determined with tissue analysis or fresh petiole-sap testing, or any other calibrated method. P The "low" diagnosis needs to be based on UF/IFAS interpretative thresholds.w lant nutritional status must be diagnosed every week to repeat supplemental application. Pv lant nutritional status must be diagnosed after each harvest before repeating supplemental fertilizer application. Pu upplemental fertilizer applications are allowed when irrigation is scheduled following a recommended method (see Chapter 3 on irrigation scheduling in Florida). S Supplemental fertilization is to be applied in addition to base fertilization when appropriate. Supplemental fertilization is not to be applied "in advance with the preplant fertilizer.t leaching rain is defined as a rainfall amount of 3 inches in 3 days or 4 inches in 7 days. As upplemental amount for each leaching rain. S
Chapter 7: Cole Crop Production in Florida Page 59 Table 7. Plant tissue analysis for cole crops. Dry wt. basis. N P K Ca Mg S Fe Mn Zn B Cu Mo Status Percent Parts per million Broccoli - Most recently matured leaf sampled at heading Deficient <3.0 0.3 1.1 0.8 0.23 0.2 40 20 25 20 3 0.04 Adequate range 3.0-4.5 0.3-0.5 1.5-4.0 0.8-2.5 0.23-0.40 0.2-0.8 40-300 25-150 45-95 30-50 5-10 0.04-0.16 High >4.5 0.5 4.0 2.5 0.40 0.8 300 150 100 100 10 0.16 Cabbage - Most recently matured leaf sampled 8 weeks after planting Deficient <3.0 0.3 2.0 0.5 0.20 0.3 30 20 30 20 3 0.3 Adequate range 3.0-6.0 0.3-0.6 2.0-4.0 0.8-2.0 0.25-0.60 0.3-0.8 30-60 20-40 30-50 20-40 3-7 0.3-0.6 High >6.0 0.6 4.0 2.0 0.60 0.8 100 40 50 40 10 0.6 Cauliflower - Most recently matured leaf sampled at buttoning Deficient <3.0 0.4 2.0 0.8 0.25 0.3 30 30 30 30 5 0.5 Adequate range 3.0-5.0 0.4-0.7 2.0-4.0 0.8-2.0 0.25-0.60 0.3-0.8 30-60 30-80 30-50 30-50 5-10 0.5-0.8 High >5.0 0.7 4.0 2.0 0.60 1.0 100 100 50 50 10 0.8 Collards - Most recently matured leaf sampled at harvest Deficient <4.0 0.3 3.0 1.0 0.40 0.3 40 40 25 25 5 0.3 Adequate range 4.0-5.0 0.3-0.6 3.0-5.0 1.0-2.0 0.40-1.00 0.3-0.8 40-100 40-100 25-50 25-50 5-10 0.3-0.8 High >5.0 0.6 5.0 2.0 1.00 0.8 100 100 50 50 10 0.8 Table 8. Sufficiency ranges for petiole sap testing for broccoli and collard. Fresh Petiole Sap Concentration (ppm) Crop Development Stage NO3-N K Six-leaf stage 800-1000 NRz One week prior to first harvest 500-800 First harvest 300-500 z NR-No recommended ranges have been developed.
Page 60 Vegetable Production HandbookTable 9. Chemical weed control in cole crops.Active ingredient Trade namelb. ai/A product/A Crops Weeds controlled / remarks*** PRETRANSPLANT and PREEMERGENCE ***Bensulide (Prefar) 4E Head & stem and leafy Annual broadleaf and grass weeds. Fair to poor control of5–6 5 – 6 qt. brassica lambsquarter, purslane, and some amaranth. Mechanical incorporate 1 to 2 in. or irrigate 2 to 4 in. deep within 36 hrs.Carfentrazone (Aim) 2 EC Head & stem and leafy Emerged broadleaf weeds. Use as a chemical fallow treat-up to 0.031 up to 2 fl. oz. brassica ment and preplant burndown application. Include a non- ionic surfactant or crop oil concentrate.DCPA (Dacthal) 75 WP Broccoli, Brussels sprouts, Can be preplant incorporated. If weeds have emerged they4.5 – 10.5 6 – 14 lb. Cauliflower, Cabbage, and must be cultivated or weeded before application. Brassica leafy vegetablesGlyphosate (various formulations) Head & stem and leafy Actively growing broadleaf and grass weeds. Use as a pre-0.3 – 1.0 brassica vegetables plant burndown.S-metolachlor (Dual Magnum) 7.62 EC Head & stem brassica Annual broadleaf and grass control. Apply immediatelymineral mineral after planting. Label is a third party registration by TPR,0.64 – 1.91 0.67 – 2.0 pt INC and grower must sign an indemnification agree- ment. Use higher rate on fine textured soils or high inmuck muck organic mater. Do not apply more than 1.91 lb ai/a of1.91 2.0 pt Dual magnum per crop on sandy soils. Chinese varieties are more sensitive to Dual Magnum injury. PHI 60 days.S-metolachlor (Dual Magnum) 7.62 EC Direct seeded cabbage Annual broadleaf and grass weeds. Label is a third partymineral mineral registration by TPR, Inc. and grower must sign an indem- nification agreement. May be applied preemergence or0.76 – 1.26 0.80 – 4.0 pt postemergence to direct seeded tight-headed cabbage.muck muck Preemergence application should be made at least 20 days1.91 – 3.82 after seeding. Apply once per crop season. At higher rates, delayed maturity can be anticipated.Oxyfluorfen (Goal 2XL) 2 EC Broccoli, Cabbage, Certain annual broadleaf weeds. Transplants less than 50.25 – 0.5 1 – 2 pt. Cauliflower, weeks old or in containers less than 1 inch square may result in more crop injury. Injury will occur as leaf cup- (Galigan) 2 E ping or crinkling. DO NOT apply in fields where acetanilide 1 – 2 pt. herbicides (Dual Magnum, Lasso, or Ramrod) have been (GoalTender, Galigan H2O) applied in the same growing season. 4E 0.5 to 1 pt. *** PREEMERGENCE / PREPLANT ***Paraquat (Gramoxone Inteon) 2.0 SL Broccoli, Cabbage, Emerged broadleaf and grass weeds. Use as a preplant0.5 – 1.0 2.0 – 4.0 pt. Cauliflower, Cavalo broc- burndown. Crop plants that have emerged will be injured. coli, Chinese cabbage, (Firestorm) 3.0 SL Turnip 1.3 – 2.7 pt.Pelargonic acid (Scythe) 4.2 EC Broccoli, Cabbage, Emerged broadleaf and grass weeds. Use as a preplant3 – 10% v/v Cauliflower, Collards, burndown. Kale, Mustard/Turnip greensTrifluralin (Treflan HFP, Trifluralin, Trifluralin Broccoli, Brussels sprouts, Annual broadleaf and grass weeds. Incorporate or irrigate 40.5 – 0.75 HF, Trilin) 4 EC Cabbage, Cauliflower inches within 8 hours. Results in Florida are erratic on soils – 1.5 pt. with low organic matter and clay contents. (Treflan) 4 L – 1.5 pt.
Chapter 7: Cole Crop Production in Florida Page 61Table 9. Continued.Active ingredient Trade namelb. ai/A product/A Crops Weeds controlled / remarks *** POSTEMERGENCE ***Carfentrazone (Aim) 2.0 EC Head & stem and leafy Emerged broadleaf weeds. Apply with a hooded sprayer to (Aim) 1.9 EW brassica row middles. Do not exceed 4.1 fl. oz./A in-season as a row middle application. PHI 0 days.up to 0.031 up to 2 fl. oz.Clethodim (Select) 2 EC Head & stem and leafy Emerged grass weeds. Include crop oil concentrate at 1%0.09 – 0.13 6 – 8 fl. oz. brassica v/v in finished spray volume. Head & stem brassica PHI 30 days. Leafy brassica PHI 14 days. (Select Max)Clopyralid (Stinger) 3 EC Cabbage, Chinese cabbage Broadleaf weeds. Do not apply more than 0.5 pt./A/year.0.09 – 0.19 0.25 – 0.5 pt. (bok choy, napa), Chinese Check plant back dates. PHI 30 days. mustard cabbageDCPA (Dacthal) 75 WP Broccoli, Brussels sprouts, Broadleaf and grass weeds. Spray over transplants without4.5 – 10.5 6 – 14 Cauliflower, Cabbage, and injury. If weeds have emerged they must be cultivated or Brassica leafy vegetables weeded before application. Can be preplant incorporated.Glyphosate (various formulations) Head & stem and leafy Broadleaf and grass weeds. Use a hooded sprayer and0.3 – 1.0 brassica direct to row middles only.Napropamide (Devrinol) 50 DF Broccoli, Brussels sprouts, Apply to transplanted crops only. If rainfall does not occur2 4 lb. Cabbage, Cauliflower within 24 hours of application, then incorporate 2 to 4 inches deep. Do not exceed 4 lb./A per crop cycle. *** POSTEMERGENCE / POSTTRANSPLANT ***Paraquat (Gramoxone Inteon) 2 SL Cabbage Emerged broadleaf and grass weeds. Direct spray solu-0.3 – 0.5 1.2 – 1.9 pt. tions to row middles only. Do not allow spray to contact crop as injury or excessive residues may result. Outer leaves should be stripped at the time of harvest. Do not apply where paraquat products have been used as preplant application.Pelargonic acid (Scythe) 4.2 EC Broccoli, Cabbage, Emerged broadleaf and grass weeds. Apply as hooded3 – 10% v/v Cauliflower, Collards, spray to row middles only. Include a residual herbicide Kale, Mustard/Turnip to broaden spectrum of weed control. greensSethoxydim (Poast) 1.5 EC Broccoli (including Annual and perennial weeds. Include a crop oil concentrate 1.5 pt Chinese and raab), or methylated seed oil in spray solution. Maximum rate or Brussels sprouts, Cabbage 3.0 pt./A per season. PHI 30 days. (Bok choy, Chinese mus- tard, napa), Cauliflower, Collards, Kale, Kohlrabi, Mustard / Rape greens
Page 62 Vegetable Production HandbookTable 10. Disease management cole crops.Cole crop fungicides and other disease management products. Ordered by FRAC group according to mode of action.Fungicide Chemical Maximum Rate/Acre Min. Days to Diseases orCode1 (active ingredients) Applic. Season Harv. Reentry Pathogens Remarks2COLE CROPSHead and Stem Crops: Broccoli, Brussels Sprouts, Cauliflower, Chinese Broccoli and Chinese Cabbage; Leafy Crops: Collards, Kale, Mustardand Turnip; and Watercress.M1 (copper compounds) SEE INDIVIDUAL 1 Varies by Alternaria leaf spot Mancozeb or maneb Many brands available: LABELS product enhances bactericidal effect from 4 hrs of fix copper compounds. Badge SC, Badge X2, to 2 days Black rot See label for restrictions Basic Copper 53, C-O- Downy Mildew and details. C-S WDG, Champ DP, Champ F2 FL, Champ WG, Champion WP, C-O-C DF, C-O-C WP, Copper Count N, Cueva, Cuprofix Ultra 40D, Kentan DF, Kocide 3000, Kocide 2000, Kocide DF, Nordox, Nordox 75WG, Nu Cop 50WP, Nu Cop 3L, Nu Cop 50DF, Nu Cop HBM2 (sulfur) SEE INDIVIDUAL 0 - Powdery mildew Products are available for Many brands available: LABELS most cole crops; See labels for restrictions and details. Cosavet DF, Kumulus DF, Micro Sulf, Microfine Sulfur, Microthiol Disperss, Sulfur 6L, Sulfur 90W, Super Six, That Flowable Sulfur, Tiolux Jet, Thiosperse 80%, Wettable Sulfur, Wettable Sulfur 92, Yellow Jacket Dusting Sulfur, Yellow Jacket Wettable SulfurM3 (maneb) SEE INDIVIDUAL 7 1 Alternaria leaf spot Not labeled for collards, Many brands available: LABELS mustard, turnip or water- Maneb 75DF, Maneb Downy mildew cress. See labels for restric- 80WP, Manex tions and details.M5 (chlorothalonil) SEE INDIVIDUAL 7 2 Alternaria leaf spot Not labeled for leafy cole Many brands available: LABELS crops or watercress. See labels for restrictions and Bravo Ultrex, Bravo Downy mildew details. Weather Stik, Chloronil 720, Echo 720, Echo 90 DF, Echo Zn, Equus 500 Zn, Equus 720 SST, Equus DF, Initiate 720, Initiate ZN2 Iprodione 4L AG 2 pts 4 pts 0 - Black leg Only labeled for broccoli Rovral 4F (broccoli) (Leptosphaeria macu- and Chinese mustard. Limit Enclosure 4 1 pt lans) on broccoli is 2 appl for broccoli and 4 (Chinese appl for Chinese mustard. Nevado 4F See labels for details. mustard) (iprodione) Alternaria leaf spot (Alternaria spp.) on Chinese mustard
Chapter 7: Cole Crop Production in Florida Page 63Table 10. Continued.Fungicide Chemical Maximum Rate/Acre Min. Days to Diseases orCode1 (active ingredients) Applic. Season Harv. Reentry Pathogens Remarks23 Monsoon 4 fl oz 16 fl oz 7 0.5 Cercospora leaf spot Not labeled for watercress Orius 3.6F or head and stem cole crops. Apply prior to infec- Toledo 3.6F Powdery mildew tion when environmental (tebuconazole) Alternaria leaf spot conditions are favorable.3 Procure 480 SC 8 fl oz 18 fl oz 0 (leafy) 0.5 Powdery mildew Not labeled for watercress. (triflumizole) 1 (head & Anthracnose See supplemental label for stem) restrictions and details.4 Ridomil Gold SL 2 pts (soil) 2 pts (soil) 7 2 Pythium & Not labeled for watercress; (mefenoxam) Phytophthora diseases Use only in a tank mix with 0.25 pts 1 pt (soil) another effective fungicide (non FRAC code 4). See (foliar) (foliar) Downy mildew label for details.4 Apron XL (mefenoxam) See label See label - 2 Pythium & Seed treatment only; Not Phytophthora diseases labeled for watercress. See (soil) label for details.4 Ultra Flourish (mefenox- 4 pts 4 pts - 2 Pythium & Soil applied as a preplant am) Phytophthora diseases treatment or following (soil) transplanting.4 Allegiance-FL (Metalaxyl) See label See label - 2 Pythium damping-off Seed treatment only. Primarly for commecerial seed treatment. See label for details.4 MetaStar 2E AG See label See label - 2 Pythium spp. Can be applied as a pre- (Metalaxyl) plant and surface applica- Phytophthora spp. tion. Do not use in green- house crops or field-grown vegetable bedding plants. See labels for details.4 + M5 Ridomil Gold Bravo 1.5 lbs See label 7 2 Alternaria leaf spot Not labeled for leafy cole Ridomil Gold Bravo SC crops or watercress. Limit (mefenoxam + chlorotha- Downy mildew is 4 applications per crop. lonil) See labels for details.7 Endura 9 oz 18 oz 0 (head and 0.5 Alternaria blight Not labeled for watercress; (boscalid) stem bras- Gray mold Limit is 2 appl/crop. See sicas) label for details. Sclerotinia rot 14 (leafy Powdery mildew green bras- Rhizoctonia rot sicas)9 + 12 Switch 62.5WG (cypro- 14 oz 56 oz 7 0.5 Alternaria blight No more than 2 sequential dinil + fludioxonil) Cercospora leaf spot appl. before rotating to a Powdery mildew different mode of action for at least 2 appl; 30 day plant back for off label crops; See label for details.9+3 Inspire Super (cyprodinil 20 fl oz 80 fl oz 7 0.5 Alternaria leaf spot Begin applications prior to + difenoconazole) disease development, and Downy mildew continue on a 7 – 10 day interval. Make no more than Powdery mildew 2 sequential applications before rotating to another effective fungicide with a different mode of action. Do not exceed 80 fl oz per season.
Page 64 Vegetable Production HandbookTable 10. Continued.Fungicide Chemical Maximum Rate/Acre Min. Days to Diseases orCode1 (active ingredients) Applic. Season Harv. Reentry Pathogens Remarks211 Quadris 15.5 fl oz 93 fl oz 0 4 hr Alternaria leaf spot Not labeled for watercress; (azoxystrobin) No more than 1 sequential appl. See label for details. Anthracnose11 Cabrio EG (pyraclos- 16 oz 64 oz 0 4 hr Black leg Not labeled for collards, trobin) kale, mustard or water- Cercospora leaf spot cress; No more than 2 sequential appl/crop. See label for details. Downy mildew Powdery mildew Rhizoctonia blight Ring spot White rust White leaf spot11 + 3 Quadris Top 14 fl oz 56 fl oz 1 0.5 Alternaria spp. No more than 1 sequential Anthracnose appl. See label for details. Cercospora leafspot Powdery mildew11 Reason 500SC 8.2 oz 24.6 oz 2 - Downy mildew Not labeled for turnip or (fenamidone) (Perenospora para- watercress. Limits are no sitica) Cercospora more than 1 sequential leaf spot (Cercospora appl. See label for details. brassicicola) White rust (Albugo candida)12 Maxim 4FS See label See label - 0.5 Fusarium and Seed treatment only; Not (fludioxonil) Rhizoctonia root rots labeled for turnip or water- cress. See label for details.14 Blocker 4F See label 30 lbs a.i. - 0.5 Club root Not labeled for leafy cole Terraclor 400 Rhizoctonia rot crops or watercress. See label for details. Terraclor 75WP Terraclor FL (PCNB)29 Omega 500F 2.6 pts 3.85 pts 20 days 2 Club root Not labeled for watercress. (Fluazinam) soil appl.; (leafy Treated turnip roots are not greens) fit for human or livestock 6.45 fl oz/ 50 days consumption. 2 day REI. 100 gal (head and See label for restrictions transplant stem) and details. drench33 Aliette 80WG 5 lbs 35 lbs 3 1 Downy mildew Not labeled for turnip or Linebacker WDG watercress. Limit is 7 appl/ crop. Do not tank mix with Legion 80WDG copper fungicides, surfac- (fosetyl-al) tants, or foliar fertilizers.
Chapter 7: Cole Crop Production in Florida Page 65Table 10. Continued.Fungicide Chemical Maximum Rate/Acre Min. Days to Diseases orCode1 (active ingredients) Applic. Season Harv. Reentry Pathogens Remarks233 Alude SEE INDIVIDUAL 0 4 hr Phythophthora spp. Not labeled for watercress. K-phite 7LP LABELS Do not apply with copper based fungicides. See label Fosphite Pythium spp. for details. Fungi-phite Fusarium spp. Helena Prophyt Rhizoctonia Phostrol Xanthomonas camp- (mono-and di-potassium estris salts of phosphorous Anthracnose acid) Downy mildew Powdery mildew40 Acrobat (dimethomorph) 6.4 oz 32 oz 0 0.5 Downy mildew Not labeled for head and stem cole crops. Only 5 appl. per season. See sup- plemental label for restric- tions and details.40 Forum 6 oz 30 oz 0 0.5 Downy mildew Not labeled for turnip or (dimethomorph) watercress. Only 5 appl. per season.40 Revus 8 fl oz 32 fl oz 1 0.5 Downy mildew Not labeled for turnip or (mandipropamid) watercress. Limit is no more than 2 sequential appl. or 4 total appl. See label for details.43 Presidio 4 fl oz 12 fl oz 2 - Downy mildew Not labeled for watercress. (fluopicolide) Phytophthora spp. Limit is no more than 2 sequential appl. or 4 total appl. per season; Use only in a tank mix with another effective fungicide; 18 month plant back for off label crops. See label for details.44 Cease SEE INDIVIDUAL 0 0.25 Xanthomonas leaf See label for details. OMRI Serenade ASO LABELS spot listed. Serenade Max Alternaria leaf spot Rhapsody (Bacillus subtilis strain Downy mildew QST 713) Powdery mildewP Actigard 50 WG 1 oz 4 oz 7 0.5 Downy Mildew Apply preventively; limit (acibenzolar-S-methyl) Black rot is 4 appl/crop on a 7-day schedule. See label for (Xanthomonas camp- details. estris suppression only)P Regalia See label See label 0 0.25 See label See label for details. OMRI (Extract of Reynoutria listed. sachalinensis)NC Actinovate See label See label 0 1 hr See label See label for details. OMRI (Streptomyces lydicus listed. WYEC 108)
Page 66 Vegetable Production HandbookTable 10. Continued.Fungicide Chemical Maximum Rate/Acre Min. Days to Diseases orCode1 (active ingredients) Applic. Season Harv. Reentry Pathogens Remarks2NC Armicarb 100 SEE INDIVIDUAL 0 4 hr Powdery mildew See label for details. Kaligreen LABELS Downy mildew Milstop Alternaria leaf spot (potassium bicarbonate) Botrytis Phoma blackleg and leafspot AnthracnoseNC Phorcephite SEE INDIVIDUAL 4 hr Phytophthora spp. No more than 6 applica- (Potassium phosphate LABELS tions per crop cycle. and phosphite) Disease prevention pro- Pythium spp. gram. See label for details. Downy Mildew Bacterial SurpressionNC Rampart SEE INDIVIDUAL 4 hr Phytophthora spp. Used as part of a disease Reveille LABELS prevention or disease con- trol program. See label for (Potassium phosphite) Pythium spp. details. Fusarium spp. Rhizcotinia Xanthomonas camp- estris Anthracnose Downy Mildew Powdery MildewNC PlantShield HC SEE INDIVIDUAL 0 0 See label See label for details. OMRI RootShield G LABELS listed. (Trichoderma harzianum Rifai strain KRL-AG2)NC Oxidate (hydrogen per- 1:100 dilu- - 0 - Alternaria leaf spot See label for details. oxide) tion Downy mildew Powdery mildewNC Sonata SEE INDIVIDUAL 0 Xanthomonas leaf See label for details. OMRI Taegro LABELS spot listed. (Bacillus sp.) Alternaria leaf spot Downy mildew Powdery mildewNC Soilgard 12G See label See label 0 0 See label See label for details. OMRI (Gliocladium virens GI-21) listed.NC Trilogy (Neem oil) See label See label 0 4 hr See label See label for details. OMRI listed.1 RAC code (fungicide group): Numbers (1-44) and letters (M, NC, U, P) are used to distinguish the fungicide mode of action groups. All fungicides within the same group (with F same number or letter) indicate same active ingredient or similar mode of action. This information must be considered for the fungicide resistance management decisions. M = Multi site inhibitors, fungicide resistance risk is low; NC = not classified, includes mineral oils, organic oils, potassium bicarbonate, and other materials of biological origin; U = Recent molecules with unknown mode of action; P = host plant defense inducers. Source: FRAC Code List 2011; http://www.frac.info/ (FRAC = Fungicide Resistance Action Committee).
Chapter 7: Cole Crop Production in Florida Page 67Table 11. Selected insecticides approved for use on insects attacking cole crops. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes Actara 1.5-5.5 oz 12 0 -head & stem aphids, flea beetles, thrips, white- 4A Do not use if other 4A insecti- (thiamethoxam) 7 - leafy flies cide has been applied. Admire Pro 4.4-10.5 fl oz 12 21 aphids, leafhoppers, foliage-feeding 4A Do not apply more than 10.5 fl (imidacloprid) thrips, whiteflies oz per acre per year. (see appropriate labels for other brands) Agree WG 0.5-2.0 lb 4 0 lepidopteran larvae (caterpillar 11 Apply when larvae are small (Bacillus thuringi- pests) for best control. Can be used ensis subspecies in greenhouse. OMRI-listed2. aizawai) *Ambush 25W3 3.2-6.4 oz 12 1 cabbage aphid (suppression), cab- 3 Do not apply more than 51.2 (permethrin) 3.2-12.8 oz – bage looper, diamondback moth3, oz/acre per season. Head and cabbage and imported cabbageworm stem Brassica crops only. Chinese cabbage only *Ammo 2.5 EC3 2.5-5.0 fl oz 12 1 armyworms, crickets, cutworms, 3 Maximum of 30 oz of product/ (cypermethrin) corn earworm, loopers, Lygus bug, acre per season. flea beetles, imported cabbage worm, leafhoppers, saltmarsh cater- pillar, stink bugs, aids in control of aphids and whiteflies *Asana XL (0.66 2.9-9.6 fl oz – 12 3-head & stem beet armyworm (aids in control), 3 Do not apply more than 0.4 EC)3 (esfenvalerate) head and stem 7-collards, mus- cabbage looper, cutworms, flea lb ai/acre per season for head Brassicas, 5.8- tard greens beetles, grasshoppers, imported and stem Brassicas or 0.2 lb 9.6 oz –collards, cabbageworm ai/acre per season for collards 9.6 – mustard and mustard greens. greens Assail 30SG 2.0-4.0 oz 12 7 aphids, thrips, whiteflies, suppres- 4A Begin applications for white- (acetamiprid) sion of diamondback moth flies when first adults are noticed. Do not apply more than 5 times per season or apply more often than every 7 days. Avaunt 2.5-3.5 oz 12 3 beet armyworm, cabbage looper, 22 Do not apply more than 14 (indoxacarb) cabbage webworm, cross-striped oz per acre per crop. Add cabbageworm, diamondback moth, a wetting agent to improve imported cabbageworm coverage. Do not use in green- house or in crops grown for transplant. Aza-Direct (azadi- 1-2 pts, up to 3.5 4 0 aphids, beetles, caterpillars, leafhop- un Antifeedant, repellant, insect rachtin) pts, if needed pers, leafminers, thrips, weevils, growth regulator. OMRI- whiteflies listed2. Azatin XL 5-21 fl oz 4 0 aphids, beetles, caterpillars, leafhop- un Antifeedant, repellant, insect (azadirachtin) pers, leafminers, thrips, weevils, growth regulator. whiteflies *Baythroid XL 0.8-3.2 fl oz 12 0 beet armyworm (1st & 2nd instar), 3 Maximum per crop season: (beta-cyfluthrin) cabbage looper, cabbage webworm, 12.8 fl oz/A. cutworms, diamondback moth larvae3, flea beetle, grasshoppers, imported cabbageworm, potato leafhopper, southern armyworm (1st & 2nd instar), stink bugs, thrips, yel- lowstriped armyworm
Page 68 Vegetable Production HandbookTable 11. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 NotesBelay 50 WDG 1.6-3.2 oz (foliar) 12 7 aphids, flea beetles, harlequin bug, 4A Do not apply more than 6.4(clothianidin) leafhoppers, stink bugs, whiteflies oz per acre per season. Do (suppression) not use an adjuvant. Toxic to bees. High rate on supplemen- tal label expiring on July 15, 2012.Belay 50 WDG 4.8 -6.4 oz 12 Apply at planting aphids, flea beetles, harlequin bug, 4A Do not apply more than 6.4 oz(clothianidin) (soil application) leafhoppers, leafminers (suppres- per acre per season. See label sion), thrips, whiteflies (suppres- for application instructions. sion)Beleaf 50 SG 2.0-2.8 oz 12 0 aphids, plant bugs 9C Do not apply more than 8.4(flonicamid) oz/acre per season. Begin applications before pests reach damaging levels.Biobit HP 0.5-2.0 lb 4 0 caterpillars (will not control large 11 Treat when larvae are young.(Bacillus thuringi- armyworms) Good coverage is essential.ensis subspecies Can be used in the green-kurstaki) house. OMRI-listed.BotaniGard 22 WP, WP: 4 0 aphids, thrips, whiteflies -- May be used in greenhouses.ES 0.5-2 lb/100 gal Contact dealer for recommen-(Beauveria bassiana) ES: dations if an adjuvant must be used. Not compatible in tank 0.5-2 qts/100 gal mix with fungicides.*Brigade 2 EC3 2.1-6.4 fl oz 12 7 aphids, armyworms, corn earworm, 3 Do not apply more than 0.4 lb(bifenthrin) crickets, cucumber beetles, cut- ai/acre for leafy or 0.5 lb ai/ worms, diamondback moth, flea acre for head and stem. beetles, ground beetles, imported cabbageworm, leafhoppers, loopers, mites, saltmarsh caterpillar, stink bugs, thrips, tobacco budworm, whiteflyCheckmate DBM-F 3.1-6.2 fl oz 0 0 diamondback moth -- For mating disruption. Does(pheromone) not affect larvae and eggs already on plants. Do not exceed 23 fl oz per acre per year.Confirm 2F 6-8 fl oz 4 7 armyworms, cabbage looper, cab- 18 If diamondback moth is also(tebufenozide) bage webworm, cross‑striped present another, or an addi- cabbageworm, garden webworm, tional, insecticide should be imported cabbageworm considered. Do not exceed 56 ounces of product per season.Coragen 3.5-5.0 fl oz 4 3 beet armyworm, cabbage looper, 28 For best results, use an(rynaxypyr) corn earworm, cross-striped cab- adjuvant when using as a bageworm, diamondback moth, foliar spray. Can be applied Hawaiian beet webworm, imported to soil at planting or by drip cabbageworm chemigation. See label for diamondback moth resistance management.Courier 40SC 9.0-13.6 fl oz 12 1 leafhoppers, planthoppers, whiteflies 16 Do not make more than 2(buprofezin) applications per crop cycle or 4 applications per year. Head and stem brassicas only.Crymax WDG 0.5-2.0 lb 4 0 caterpillars 11 Use high rate for armyworms.(Bacillus thuringi- Treat when larvae are young.ensis subspecieskurstaki)
Chapter 7: Cole Crop Production in Florida Page 69Table 11. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes *Danitol3 10.67-16 fl oz 24 7 cabbage looper, imported cabbage- 3 Do not apply more than 42.67 (fenpropathrin) worm, yellowstriped armyworm fl oz per acre per season. Head and stem brassicas only. Deliver 0.25-1.5 lb 4 0 caterpillars 11 Use higher rates for army- (Bacillus thuringi- worms. OMRI-listed2. ensis subspecies kurstaki) *Diazinon AG-500, AG500 preplant: 96 preplant cutworms, mole crickets, wire- 1B Broccoli, cabbage, cauli- *50 W 1-4 qt worms flower, collard, kale, mustard (diazinon) 50W: 2-8 lb greens. See label for depth to incorporate. *Dibrom 8 EC 1 pt 48 1 aphids, diamondback moth, import- 1B Apply no more than 1 pt per (naled) ed cabbageworm acre in Florida. Do not apply more than 10 pt per acre per season. Broccoli, cabbage, cauliflower, Brussels sprouts, kale and collards. Dimethoate 4 EC 0.5-1 pt – broc- 48 7 – broccoli, aphids 1B Highly toxic to bees. For broc- (dimethoate) coli, cauliflower; cauliflower, coli, cauliflower, kale, turnip 0.5 pt – kale, 14 – kale, mus- greens and roots, and mus- mustard greens, tard greens, tard greens only. turnip turnip *Dimilin 2L 2-4 fl oz 12 7 grasshoppers 15 All Brassica crops. No more (diflubenzuron) than 4 applications per sea- son. May be applied only to turnip varieties that do not produce a harvestable root. DiPel DF 0.5-2.0 lb 4 0 caterpillars 11 Treat when larvae are young. (Bacillus thuringi- Good coverage is essential. ensis subspecies OMRI-listed2. kurstaki) *Di-Syston 8 EC 1.1-2.1 fl 48 42 aphids, flea beetles, root aphids 1B Cabbage and tight-heading (disulfoton) oz/1000 ft of row Chinese cabbage only - soil application. Durivo 10-13 fl oz 12 30 aphids, caterpillars, flea beetles, 4A, 28 May be applied via one of sev- (thiamethoxam, thrips, whiteflies eral different soil applications chlorantraniliprole) methods. Entrust 0.5-3 oz 4 1 armyworms, cabbage looper, 5 See label for resistance man- (spinosad) diamondback moth, imported cab- agement. Do not apply more bageworm, leafminers, thrips, sup- than 9 oz per acre per crop. pression of flea beetles OMRI-listed2. Esteem Ant Bait 1.5-2.0 lb 12 1 red imported fire ant 7C Apply when ants are actively (pyriproxyfen) foraging. Extinguish 1.0-1.5 lb 4 0 fire ants 7A Slow‑acting IGR (insect ((S)-methoprene) growth regulator). Best applied early spring and fall where crop will be grown. Colonies will be reduced after three weeks and eliminated after 8 to 10 weeks. May be applied by ground equipment or aerially.
Page 70 Vegetable Production HandbookTable 11. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 NotesFulfill 2.75 oz 12 7 cabbage aphid, green peach aphid, 9B Apply when aphids and white-(pymetrozine) turnip aphid, suppression of white- flies first appear. Provides flies suppression of whiteflies. Maximum of 2 applications per crop.Intrepid 2F 4-16 fl oz, 4 1 beet armyworm, cabbage looper, 18 Do not apply more than 64 oz(methoxyfenozide) depending on cabbageworm, cross-striped cab- per acre per season. pest bageworm, fall armyworm garden webworm, imported cabbageworm, southern armyworm, true army- worm, yellowstriped armywormJavelin WG 0.12-1.50 lb 4 0 most caterpillars, but not 11 Treat when larvae are young.(Bacillus thuringi- Spodoptera species (armyworms) Thorough coverage is essen-ensis subspecies tial. OMRI-listed2. See label forkurstaki) crops (most cole crops).Knack 8-10 fl oz 12 7 whiteflies (immatures) 7C Limited to 2 applications per(pyriproxyfen) season.Kryocide 8-16 lb 12 depends on crop cabbage looper, cutworms, diamond un Do not exceed 96 lb per acre(cryolite) 7-14 back moth, flea beetles, imported per season. (broccoli, cab- cabbage worm, yellowstriped army- bage, cauliflower, collards, worm kohlrabi)*Lannate LV; *SP LV: 0.75-3.0 pt 48 Cabbage – 1, Beet armyworm, diamondback 1A Do not make more than 10(methomyl) SP: 0.25-1 lb broccoli and moth, fall armyworm, imported cab- applications per crop (8 for cauliflower – 3, bageworm, loopers, variegated cut- collards, kale, mustard and others –10 worm (pests vary by specific crop) turnip greens). For use on broccoli, cabbage, cauli- flower, Chinese cabbage, fresh market collards, kale, mustard and turnip greens.*Larvin 3.2 16-40 fl oz 48 7 beet armyworm, cabbage looper, 1A Do not exceed more than 4.0(thiodicarb) diamondback moth, flea beetles, lb active ingredient per acre imported cabbageworm per season. (160 fl oz) For broccoli, cabbage, and cauli- flower only.Lorsban 75WG, Foliar: 24, 72 21 Armyworms (including beet army- 1B For use on broccoli, cabbage,(chlorpyrifos) 0.67-1.33 lb for cauli- worm), cabbage aphid, cutworms, cauliflower, collards, kale, flower striped flea beetle, imported cab- kohlrabi. See label for specific bageworm crop directions.Lorsban 15G, See labels for 24, 72 30 root maggots. If preplant (Lorsban 1B Only one application per sea-75WG, Advanced rates for soil for cauli- Advanced), also billbugs, cutworms, son. See label for restrictions application flower grubs, symphylans, wireworms and specific crop directions.Malathion 8F 1.5-2.5 pt 12 7, except broc- aphids, cabbage looper, imported 1B(malathion) coli (3) cabbagewormMovento 4-5 fl oz 24 1 aphids, whiteflies 23 Limited to 10 oz/acre per(spirotetramat) season.M-Pede 49% EC 1-2 % V/V 12 0 aphids, leafhoppers, mites, thrips, -- OMRI-listed2.(soap, insecticidal) whiteflies*MSR Spray 1.5-2 pt 7 days 7 aphids, thrips 1B Broccoli, broccoflower, broc-Concentrate (oxy- colini, cabbage, cauliflowerdemeton-methyl) - See label for restrictions.*Mustang 2.4-4.3 oz 12 1 aphids (some), armyworms, cab- 3 Do not make applications(zeta-cypermethrin) bage looper, cabbage webworm, less than 7 days apart. corn earworm, crickets, cucumber Diamondback moth popula- beetles, cutworm, flea beetles, tions in Florida have been grasshoppers, imported cabbage- found to be resistant to pyre- worm, leafhoppers, saltmarsh cater- throids. pillar, southern cabbageworm, stink bugs, aids in control of whiteflies
Chapter 7: Cole Crop Production in Florida Page 71Table 11. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes Neemix 4.5 4-16 fl oz 12 0 aphids, armyworms, cabbage loop- un IGR and feeding repellant. (azadirachtin) er, caterpillars, cutworms, diamond- Greenhouse and field. OMRI- back moth, dipterous leafminers, listed2. leafminers, imported cabbageworm, thrips, whiteflies Oberon 2 SC 7.0-8.5 fl oz 12 7 whiteflies 23 Maximum amount per crop: (spiromesifen) 25.5 fl oz/acre. No more than 3 applications. Not for turnip greens. Platinum 5.0-11 fl oz 12 30 aphids, flea beetles, thrips, white- 4A Soil application. Platinum 75SG 1.66-3.67 oz flies (thiamethoxam) *Pounce 25 WP3 See label for 12 1 armyworms, cabbage looper, dia- 3 Broccoli, cabbage, cauli- (permethrin) crop-specific mondback moth, imported cabbage- flower, Chinese broccoli, col- rates. worm, plant bugs, thrips lards, turnips. *Proaxis 1.92-3.84 fl oz 24 1 aphids(2), armyworm, beet army- 3 (1) First and second instars Insecticide3 worm(1), cabbage looper, cab- only. (gamma-cyhalothrin) bage webworm, corn earworm, (2)Suppression only. cutworms, diamondback moth, Do not apply more than 1.92 fall armyworm(1), flea beetles, pints per acre per season. grasshoppers, imported cabbage- worm, leafhoppers, southern cab- bageworm, spider mites(2), stink bugs, thrips(2), vegetable weevil Head and stem brassicas (adult), whiteflies(2), yellowstriped only. armyworm *Proclaim 2.4-4.8 oz 12 7 - head & stem beet armyworm, cabbage webworm, 6 Do not make more than (emamectin benzo- corn earworm, cross-striped cab- 2 sequential applications ate) bageworm, diamondback moth, fall without rotating to another 14 - leafy armyworm, imported cabbageworm, product with a different mode loopers, suppression of Liriomyza of action. Do not apply by leafminers aircraft. Not for turnips grown for roots. Provado 1.6F (imi- 3.8 oz 12 7 aphids, whiteflies 4A Do not apply more than 0.5 lb dacloprid) ai per year. Pyganic 5.0 4.5-18 oz 12 0 insects 3 Harmful to bees. Can be used (pyrethrins) in greenhouses. OMRI-listed.2 Radiant SC 5-10 fl oz 4 1 armyworms, cabbage looper, dia- 5 Do not apply to seedlings (spinetoram) mondback moth, imported cabbage- grown for transplant. worm, Liriomyza leafminers, thrips Requiem 25EC 2-4 qt (no more 4 0 green peach aphid, turnip aphid, un (extract of than 2% v/v) whiteflies Chenopodium ambrosioides) Rimon 0.83 EC 6-12 fl oz 12 7 armyworms, cabbage looper, cab- 15 No more than 3 applications (novaluron) bage webworm, corn earworm, or 24 fl oz per acre per sea- cucumber beetles, diamondback son. No more than 2 applica- moth, imported cabbageworm, lepi- tions for thrips or whiteflies. dopteran and dipteran leafminers, Head and stem Brassica only. stink bugs, vegetable weevil, thrips, whiteflies Saf-T-Side, others 1-2 gal/100 gal 4 up to day of aphids, leafhoppers, mites, plant -- OMRI-listed2. (Oil, insecticidal) harvest bugs, thrips, whiteflies
Page 72 Vegetable Production HandbookTable 11. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 NotesSevin 80S; XLR, 4F 80S: 0.63-2.5 lb 12 3 or 14, depend- armyworms, corn earworm, dia- 1A Up to 4 applications, at least(carbaryl) XLR, 4F: ing on specific mondback moth, flea beetles, harle- 7 days apart. See label for crop quin bug, imported cabbage worm, specific crops. 0.5-2 qts leafhoppersSynapse 3-5 oz 12 1 armyworms, cabbage webworm, 28 Do not apply more than(flubendiamide) corn earworm, cross-striped cab- 4 oz/acre per season. bageworm, diamondback moth, Supplemental label adds tur- garden webworm, imported cab- nip greens and higher rates bageworm, loopers, saltmarsh (3-5 oz). caterpillar*Telone C-35 See label 5 days ‑ preplant symphylans, wireworms -- See supplemental label for(dichloropropene + See label use restrictions for south andchloropicrin) central Florida.*Telone II(dichloropropene)*Thionex 3EC 1-1.33 qt 96 cabbage – 17, armyworms, cabbage aphid, cab- 2 Do not make more than 2*Thionex 50W 1.5-2.0 lb broccoli and bage looper, cross-striped cab- applications per season or cauliflower— bageworm, cutworms, diamondback exceed 2.0 lb ai/acre per only use if moth, flea beetles, harlequin bug, season. For broccoli, cab-(endosulfan) product has imported cabbageworm, leafhop- bage, cauliflower. Broccoli older label and pers, stink bugs, whiteflies and cauliflower not on new then only until product label (9/24/10) and 7/31/12 thus cannot be treated with cabbage–21 for new product. Do not use on 50W any of these crops after July 31, 2012.*Thionex 3EC 1-1.33 qt, except 48 21 armyworms, aphids, cabbage loop- 2 Do not make more than one(endosulfan) kale (1 qt) er, diamondback moth, flea beetles, application per season or harlequin bug, imported cabbage- apply more than 1.0 lb ai/acre worm, whitefly per season (0.75 lb for kale). For collards, mustard greens, kale. Do not use after July 31, 2012. These uses not on new product label (9/24/10), so only older product can be used (with older label).Trigard 2.66 oz 12 7 leafminers 17 Limited to 6 applications.(cyromazine) Includes turnip greens, not grown for roots.Trilogy 0.5-2% V/V 4 0 aphids, mites, suppression of thrips un Apply morning or evening to(extract of neem oil) and whiteflies reduce potential for leaf burn. Toxic to bees exposed to direct treatment. OMRI-listed2.Venom Insecticide foliar: 1-4 oz 12 foliar - 1 Foliar: brown stink bug, suppression 4A Use one application method,(dinotefuran) soil: 5-6 oz soil - 21 of cabbage aphid, flea beetle, grass- not both (soil or foliar). hopper, suppression of green peach Foliar: Do not apply more aphid, green sink bug, harlequin than 0.268 lb ai per acre per bug, southern green stink bug season.Venom 20 SG foliar: 0.44- Soil: suppression of green peach 0.895 lb Soil: Do not apply more than aphid and cabbage aphid, leafminer, 0.536 lb ai per acre per sea- soil: 1.13-1.34 lb whiteflies son. For head and stem brassicas only.Voliam Flexi 4-7 oz 12 head and stem – aphids, beet armyworm, cabbage 4A, 28 Highly toxic to bees exposed(thiamethoxam and 3, leafy Brassica looper, cabbage webworm, corn to direct treatment or residueschlorantraniliprole) greens - 7 earworm, diamondback moth, fall on blooming crops. armyworm, flea beetles, imported cabbageworm, thrips, whitefly, yel- lowstriped armyworm
Chapter 7: Cole Crop Production in Florida Page 73Table 11. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes *Warrior II3 (lamb- 0.96-1.92 fl oz 24 1 aphids(1), armyworm(2), beet cab- 3 Do not apply more than 0.24 da‑cyhalothrin) bage looper, cabbage webworm, lb ai/acre per season. corn earworm, cutworms, diamond- (1)suppression back moth, fall armyworm(2), flea only (2)1st and 2nd instar only beetles, grasshoppers, imported cabbageworm, leafhoppers, plant bugs, stink bugs, thrips(1), white- For head and stem Brassicas flies(1), yellowstriped armyworm only. Xentari DF 0.5-2.0 lb 4 0 caterpillars 11 Treat when larvae are young. (Bacillus thuringi- Thorough coverage is essen- ensis subspecies tial. May be used in the green- aizawai) house. Can be used in organic production. The pesticide information presented in this table was current with federal and state regulations at the time of revision. The user is responsible for determining the intended use is consistent with the label of the product being used. Use pesticides safely. Read and follow label instructions. 1Mode of Action codes for vegetable pest insecticides from the Insecticide Resistance Action Committee (IRAC) Mode of Action Classification v. 6.1 August 2008. 1A. Acetyl cholinesterase inhibitors, Carbamates (nerve action) 1B. Acetyl cholinesterase inhibitors, Organophosphates (nerve action) 2A. GABA‑gated chloride channel antagonists (nerve action) 3. Sodium channel modulators (nerve action) 4A. Nicotinic acetylcholine receptor agonists (nerve action) 5. Nicotinic acetylcholine receptor allosteric activators (nerve action) 6. Chloride channel activators (nerve and muscle action) 7A. Juvenile hormone mimics (growth regulation) 7C. Juvenile hormone mimics (growth regulation) 9B and 9C. Selective homopteran feeding blockers 10. Mite growth inhibitors (growth regulation) 11. Microbial disruptors of insect midgut membranes 12B. Inhibitors of mitochondrial ATP synthase (energy metabolism) 15. Inhibitors of chitin biosynthesis, type 0, lepidopteran (growth regulation) 16. Inhibitors of chitin biosynthesis, type 1, homopteran (growth regulation) 17. Molting disruptor, dipteran (growth regulation) 18. Ecdysone receptor agonists (growth regulation) 22. Voltage‑dependent sodium channel blockers (nerve action) 23. Inhibitors of acetyl Co‑A carboxylase (lipid synthesis, growth regulation) 28. Ryanodine receptor modulators (nerve and muscle action) un. Compounds of unknown or uncertain mode of action 2 OMRI-listed: Listed by the Organic Materials Review Institute for use in organic production. 3 Diamondback moth in Florida has been found to be resistant to pyrethroids. * Restricted Use Only.
Page 74 Vegetable Production HandbookTable 12. Selected insecticides approved for use on insects attacking turnips.Trade Name Rate REI Days To MOA(Common Name) (product/acre) (Hours) Harvest Insects Code1 NotesActara 1.5-4.0 oz 12 7 aphids, flea beetles, leafhop- 4A Use higher rate for whiteflies. For(thiamethoxam) pers, whiteflies turnips grown for roots. Do not exceed 8 oz/acre per season.Admire Pro 4.4-10.5 fl oz 12 21 aphids, flea beetles, leafhop- One application, no more than 10.5(imidacloprid) pers, thrips, whiteflies oz/acre. Greens may be used for food.Agree WG 0.5-2.0 lb 4 0 lepidopteran larvae (caterpil- 11 Apply when larvae are small for best(Bacillus thuringiensis sub- lar pests) control.species aizawai)*Ambush 25W2 3.2-6.4 oz 12 1 cabbage aphid (suppres- 3 Do not exceed 4 applications. Do(permethrin) sion), cabbage looper, not graze treated areas or feed crop diamondback moth (larvae), refuse to livestock. For turnips imported cabbageworm grown for roots.*Asana XL (0.66 EC) 5.8-9.6 fl oz 12 7 armyworm, flea beetles, 3 Do not apply more than 0.4 lb ai per(esfenvalerate) imported cabbageworm acre per season.Avaunt 2.5-3.5 oz 12 3 beet armyworm, cabbage 22 For turnip greens only, not for tur-(indoxacarb) looper, cabbage webworm, nips grown for roots. Do not apply cross-striped cabbageworm, more than 14 oz per acre per crop. diamondback moth, import- ed cabbagewormAza-Direct 1-2 pt, up to 3.5 4 0 aphids, beetles, caterpillars, un Antifeedant, repellant, insect growth(azadirachtin) pt, if needed leafhoppers, leafminers, regulator. OMRI-listed3. mites, stink bugs, thrips, weevils, whitefliesAzatin XL 5-21 fl oz 4 0 aphids, beetles, caterpillars, un Antifeedant, repellant, insect growth(azadirachtin) leafhoppers, leafminers, regulator. thrips, weevils, whiteflies*Baythroid XL2 0.8-3.2 fl oz 12 0 beet armyworm (1st & 2nd 3 Maximum amount per season - 12.8(beta-cyfluthrin) instar), cabbage looper, fl oz/A. cabbage webworm, cut- For use on turnip greens only, not worms, diamondback moth for turnips grown for roots. larvae, fall armyworm (1st & 2nd instar), grasshoppers, imported cabbageworm, southern armyworm (1st & 2nd instar), thrips, yellow- striped armywormBelay 50 WDG 1.6-3.2 oz – foliar 12 7 – foliar aphids, flea beetles, harle- 4A A supplemental label that expires(clothianidin) 4.8-6.4 oz – soil at planting quin bug, leafhoppers, stink July 15, 2012 covers rates above 2.1 – soil bugs, suppression of white- oz for foliar applications. For turnip flies, thrips (soil only) greens only.Beleaf 50 SG 2.0-2.8 oz 12 3 aphids, plant bugs 4A No more than 3 applications at high(flonicamid) rate per season.Biobit HP 0.5-2.0 lb 4 0 caterpillars (will not control 11 Treat when larvae are young. Good(Bacillus thuringiensis sub- large armyworms) coverage is essential. Can be used inspecies kurstaki) the greenhouse. OMRI-listed3.BotaniGard 22 WP, ES WP: 4 0 aphids, thrips, whiteflies -- May be used in greenhouses.(Beauveria bassiana) 0.5-2 lb/100 gal Contact dealer for recommendations if an adjuvant must be used. Not ES: compatible in tank mix with fungi- 0.5-2 qt/100 gal cides.
Chapter 7: Cole Crop Production in Florida Page 75Table 12. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes *Brigade 2EC2 2.1-6.4 fl oz 12 7 aphids, armyworms, corn 3 Turnip greens only. earworm, crickets, cucum- ber beetles, cutworms, flea beetles, grasshoppers, imported cabbageworm, loopers, mites, saltmarsh caterpillar, stink bugs, thrips, whitefly Checkmate DBM-F 3.1-6.2 fl oz 0 0 diamondback moth -- For mating disruption. Does not (pheromone) affect eggs and larvae already on plants. Confirm 2F 6-8 fl oz 4 7 armyworms, cabbage 18 If diamondback moth is also present (tebufenozide) looper, cabbage webworm, another, or an additional, insecticide cross-striped cabbageworm, should be considered. Do not exceed garden webworm, imported 56 ounces of product per acre per cabbageworm season. Coragen 3.5-5.0 fl oz 4 1 beet armyworm 28 Foliar application only. Make no (chlorantraniliprole) more than 4 applications per crop or exceed 15.4 fl oz of product per acre per crop. Crymax WDG 0.5-2.0 lb 4 0 caterpillars 11 Use high rate for armyworms. Treat (Bacillus thuringiensis sub- when larvae are young. species kurstaki) Deliver 0.25-1.5 lb 4 0 caterpillars 11 Use higher rates for armyworms. (Bacillus thuringiensis sub- OMRI-listed3. species kurstaki) Dimethoate 4EC 0.5 pt 48 14 aphids, leafhoppers, 1B Highly toxic to bees. No more than (dimethoate) leafminers 3 applications per year. *Dimilin 2L 2-4 oz 12 7 grasshoppers 15 Dimilin is an insect growth regula- (diflubenzuron) tor – insects must ingest and molt before effects are seen. Apply when grasshoppers are in the 2nd to 3rd nymphal stage. Turnip greens only. Do not use on turnip cultivars that produce a harvestable root. DiPel DF 0.5-2.0 lb 4 1 caterpillars 11 Treat when larvae are young. Good (Bacillus thuringiensis sub- coverage is essential. OMRI-listed3. species kurstaki) Entrust 0.5-3.0 oz 4 1 - greens armyworms, cabbage 5 Do not apply to cole crops grown (spinosad) (greens) looper, diamondback moth, within a greenhouse or screenhouse imported cabbageworm, for transplant. OMRI-listed3. 3 - roots leafminers, thrips 1.0-2.0 oz (roots) Extinguish 1.0-1.5 lb 4 0 fire ants 7A Slow-acting IGR (insect growth ((S)-methoprene) regulator). Best applied early spring and fall where crop will be grown. Colonies will be reduced after three weeks and eliminated after 8 to 10 weeks. May be applied by ground equipment or aerially. Fulfill 2.75 oz 12 7 cabbage aphid, green peach 9B Apply when aphids and whiteflies (pymetrozine) aphid, turnip aphid, white- first appear. Maximum of 2 applica- flies (suppression) tions per crop. Greens only.
Page 76 Vegetable Production HandbookTable 12. Continued.Trade Name Rate REI Days To MOA(Common Name) (product/acre) (Hours) Harvest Insects Code1 NotesIntrepid 2F 4-16 fl oz if 4 1 - greens beet armyworm, cabbage 18 Do not apply more than 64 oz per(methoxyfenozide) grown for greens 14 - roots looper, cabbageworm, acre per season. 6-16 fl oz if cross-striped cabbageworm, grown for roots fall armyworm garden web- worm, imported cabbage- worm, southern armyworm, true armyworm, yellow- striped armywormJavelin WG 0.12-1.50 lb 4 0 most caterpillars, but not 11 Roots only. Treat when larvae are(Bacillus thuringiensis sub- Spodoptera species (army- young. Thorough coverage is essen-species kurstaki) worms) tial. OMRI-listed3.Knack IGR 8 fl oz 12 3 whiteflies 7D Insect growth regulator has no effect(pyriproxyfen) on adult whiteflies. Do not make more than 2 applications per grow- ing season and wait at least 14 days between applications. Turnips grown for roots only.*Lannate LV, *SP (metho- LV: 1.5-3.0 pt 48 10 beet armyworm, cabbage 1A Greens only.myl) SP: 0.5-1.0 lb looper, cabbageworm, dia- mondback moth (larvae), imported cabbagewormLepinox WDG 1.0-2.0 lb 12 0 for most caterpillars, includ- 11 Treat when larvae are small.(Bacillus thuringiensis sub- ing beet armyworm (see Thorough coverage is essential.species kurstaki) label)Lorsban 15G, 75WG See labels for 24 30 root maggots 1B One soil application per season.(chlorpyrifos) ratesMalathion 57 EC 1-2 pt 12 1 aphids, cabbage looper, 1B Apply no more than 3 times per sea-(malathion) imported cabbageworm son. Minimum retreatment interval for greens is 5 days and for roots, 7 days.M-Pede 49% EC 1-2% V/V 12 0 aphids, leafhoppers, mites, -- OMRI-listed2.(Soap, insecticidal) plant bugs, thrips, whiteflies*Mustang2 2.4-4.3 oz – 12 1 aphids, armyworms, cab- 3 Use no more than 25.8 oz of product(zeta-cypermethrin) greens bage webworm, corn ear- per acre per season. 1.4-4.3 oz – worm, crickets, cucumber roots beetles, cutworms, flea beetles, grasshoppers, ground beetles, imported cabbageworm, leafhop- pers, loopers, Lygus bugs, saltmarsh caterpillar, stink bugs, tobacco budworm, vegetable weevil, whiteflies, wireworm adultsNeemix 4.5 EC (azadi- 4-16 fl oz 12 0 aphids, armyworms, cab- un IGR and feeding repellant.rachtin) bage looper, cutworms, Greenhouse and field use. diamondback moth (larvae), OMRI-listed3. imported cabbageworm, leafminers, thrips, whitefliesPlatinum 5-12 fl oz 12 at planting aphids, flea beetles, leafhop- 4A Roots only. Do not exceed a total ofPlatinum 75SG 1.7-4.01 oz pers, whiteflies 12 fl oz per acre per season or 4.01 oz (75SG).(thiamethoxam)
Chapter 7: Cole Crop Production in Florida Page 77Table 12. Continued. Trade Name Rate REI Days To MOA (Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes *Pounce 25 WP2 (perme- 3.2-9.6 oz 12 1 aphids (suppression), 3 Do not apply more than 0.45 lb ai/ thrin) armyworms, beet army- acre per season. worm, cabbage looper, corn earworm, cutworms, diamondback moth (larvae), fall armyworm, imported cabbageworm, leafhop- pers, leafminers, southern armyworm, southern white butterfly *Proclaim 2.4-4.8 oz 12 14 beet armyworm, cabbage 6 Greens only. (emamectin benzoate) webworm, corn earworm, cross-striped cabbageworm, diamondback moth, fall armyworm, imported cab- bageworm, cabbage looper, suppression of Liriomyza leafminers Provado 1.6F 3.5 oz 12 7 aphids, flea beetles, white- 4A Do not use in conjunction with (imidacloprid) flies Admire. Maximum of 10.5 fl oz. per acre per season. Pyganic Crop Protection 4.5-18 fl oz 12 0 aphids, beetles, caterpillars, 3 Pyrethrins degrade rapidly in sun- EC 5.0 crickets, grasshoppers, light, but still may be harmful to (pyrethrins) leafhoppers, leafminers, bees. OMRI-listed3 mites, stink bugs, thrips, whiteflies, Radiant 6-8 - roots 4 3 armyworms, diamondback 5 See label. (spinetoram) 5-10 - tops moth, imported cabbage- worm, Liriomyza leafminers, loopers, thrips Sevin XLR; 4F 0.5-2.0 qt 12 14 – armyworms, aster leafhop- 1A Do not apply more than a total of 7.5 (carbaryl) greens per, corn earworm, fall lb or 6 qt per acre per crop. 7 – roots armyworm, flea beetles, leafhoppers, Lygus bug, spittlebugs, stink bug, tar- nished plant bug Sulfur 80% W, others See label 24 mites -- Synapse WG 3-5 oz 12 1 armyworms, cabbage 28 Greens only. Not for turnips grown (flubendiamide) looper, cabbage webworm, for roots. Do not apply more corn earworm, cross-striped than 15 oz per acre per season. cabbageworm, cutworms, Supplemental label expires 9-23- diamondback moth, gar- 2012. den webworm, imported cabbageworm, saltmarsh caterpillar, southern cab- bageworm *Telone C-35 (dichloropro- See label 5 days ‑ preplant symphylans, wireworms -- See supplemental label for use pene + chloropicrin) See label restrictions in south and central Florida. *Telone II (dichloropropene) Trigard 2.66 oz 12 7 leafminers 17 Limited to 6 applications. Turnip (cyromazine) greens only.
Page 78 Vegetable Production HandbookTable 12. Continued.Trade Name Rate REI Days To MOA(Common Name) (product/acre) (Hours) Harvest Insects Code1 NotesTrilogy 0.5-2.0% V/V 4 0 aphids, mites, suppression un Apply morning or evening to reduce(extract of neem oil) of thrips and whiteflies potential for leaf burn. Toxic to bees exposed to direct treatment. OMRI- listed3.Xentari DF 0.5-2.0 lb 4 0 caterpillars 11 Treat when larvae are young.(Bacillus thuringiensis sub- Thorough coverage is essential. Mayspecies aizawai) be used in the greenhouse. Can be used in organic production.The pesticide information presented in this table was current with federal and state regulations at the time of revision. The user is responsible for determining the intendeduse is consistent with the label of the product being used. Use pesticides safely. Read and follow label instructions.1Mode of Action codes for vegetable pest insecticides from the Insecticide Resistance Action Committee (IRAC) Mode of Action Classification v. 6.1 August 2008. 1A. Acetyl cholinesterase inhibitors, Carbamates (nerve action) 1B. Acetyl cholinesterase inhibitors, Organophosphates (nerve action) 2A. GABA‑gated chloride channel antagonists (nerve action) 3. Sodium channel modulators (nerve action) 4A. Nicotinic acetylcholine receptor agonists (nerve action) 5. Nicotinic acetylcholine receptor allosteric activators (nerve action) 6. Chloride channel activators (nerve and muscle action) 7A. Juvenile hormone mimics (growth regulation) 7C. Juvenile hormone mimics (growth regulation) 9B and 9C. Selective homopteran feeding blockers 10. Mite growth inhibitors (growth regulation) 11. Microbial disruptors of insect midgut membranes 12B. Inhibitors of mitochondrial ATP synthase (energy metabolism) 15. Inhibitors of chitin biosynthesis, type 0, lepidopteran (growth regulation) 16. Inhibitors of chitin biosynthesis, type 1, homopteran (growth regulation) 17. Molting disruptor, dipteran (growth regulation) 18. Ecdysone receptor agonists (growth regulation) 22. Voltage‑dependent sodium channel blockers (nerve action) 23. Inhibitors of acetyl Co‑A carboxylase (lipid synthesis, growth regulation) 28. Ryanodine receptor modulators (nerve and muscle action) un. Compounds of unknown or uncertain mode of action2 Avoid pyrethroids if diamondback moth is a problem. Larvae have been shown to be resistant.3 OMRI listed: Listed by the Organic Materials Review Institute for use in organic production. * Restricted Use Only.
Chapter 7: Cole Crop Production in Florida Page 79Table 13. Breakeven production costs for cabbage at various yield levels in the Hastings, FL area, 2008-2009. Yield (50 lb units/acre) Cost per acre 660 680 700 720 740 Variable Costs $1,794.37 $2.72 $2.64 $2.56 $2.49 $2.42 Fixed Costs $690.52 $1.05 $1.02 $0.99 $0.96 $0.93 Harvest Cost/unit $3.70 $3.70 $3.70 $3.70 $3.70 Total Cost/unit $7.46 $7.35 $7.25 $7.15 $7.06
Chapter 8. 2012-2013Production of Major Asian Vegetables in FloridaM.L. Lamberts, E.J. McAvoy, D.D. Sui, A.J. Whidden and C.A. Snodgrass The term “Asian Vegetable” is a broad one which CUCURBITSencompasses both the vegetables grown in the countriesthat comprise Asia and those eaten by people of Asian This group (Tables 2a and 2b) includes, eaten eitherextraction or who like Asian cuisine. Since many of the immature or mature, and several vegetables with ediblevegetables which are described in this chapter are members tender stems and leaves. All can be grown on raised beds,of families that are covered in depth in other chapters in with or without plastic mulch, and with drip, overhead orthis volume, that information will not be duplicated. subsurface irrigation. Most of the crops are trellised, pri- marily to maximize space, minimize bud drop and fruit rot caused by over shading and exposure to soil moisture and diseases and promote straight fruit. Winter melon is the CRUCIFERS exception since it is generally too heavy to trellis. Fertilizer This group (Tables 1a and 1b) includes primarily crops recommendations for cucumbers (Chapter 9) are applicablewith edible leaves, with the exception of kohlrabi where for fuzzy melon, long gourd, both luffas, bittermelon andthe swollen stem is consumed and daikon which is an snake gourd. Recommendations for watermelon (Chapteredible root. They can be grown on raised beds without 9) should be followed for winter melon and chayote. Withmulch (or with mulch if it is cost effective) and with the exception of chayote, where the entire fruit is planted,drip, overhead or subsurface irrigation. Fertilizer recom- these crops are started from seed and grown as transplantsmendations for these crops are found in Chapter 7 under prior to being set in the field. For pest control products,broccoli, cabbage or Chinese cabbage, except for daikon these crops are included in Crop Group 9 (Cucurbitwhich is in Chapter 18. For pest control products, these Vegetables).crops are included in Crop Group 5 [Brassica (Cole) LeafyVegetables]. The exception is daikon, which is in Crop BOTANYGroup 1 (Root and Tuber Vegetables) and is covered in NomenclatureChapter 18. Bittermelon (Chinese and Indian types) - Momordica charantia BOTANY Nomenclature Chayote - Sechium edule Family – Brassicaceae (Cruciferae) Fuzzy melon (immature fruit) and winter melon (mature Cabbage, flat - Brassica oleracea var. capitata fruit) - Benincasa hispida Chinese broccoli / gailan or gai lan / kailan or kai lan / Long gourd (oopoh) - Lagenaria sicerariaflowering kale - Brassica oleracea var. alboglabra Angled luffa (silk squash) - Luffa acutangula Chinese cabbage [includes: napa (tight headed) and chi- Smooth luffa - Luffa aegyptica (cylindrica)hili (semi-loose headed)]- Brassica rapa var. pekinensis Snake gourd - Trichosanthes cucumerina Chinese mustard (includes: bok choi , Shanghai choi/ baby bok choi, yuchoi / yuchoy / u-choi /choy sum -Brassica rapa subsp. chinensis Kohlrabi - Brassica oleracea var. gongylodes Oriental radish: Daikon (Japanese) / lobok or lo bok(Chinese) - Raphanus sativus var. longipinnatus Page 81
Page 82 Vegetable Production HandbookTable 1a. Varieties of Asian Brassicas Crop Varieties Cabbage, flat Drumhead, KK Cross, KY Cross Chinese broccoli / gailan / flowering kale Green Lance Chinese cabbage napa (tight-headed) China Express, China Pride chihili [semi-loose headed] Michihili, Monument, Jade Pagoda Chinese mustard bok choi Canton Choice, Ching-Chiang, Hybrid Lucky choi, Long White, Short White Shanghai choi / baby bok choi Dynasty, Shanghai Green yuchoi / yuchoy / u-choi /choy sum Dwarf, Extra Dwarf, Kohlrabi Peking, Purple Oriental radish Daikon (Japanese): Everest, Hybrid Everest, Mikura Cross, Mino Early, Relish Lobok / lo bok (Chinese): Red MeatTable 1b. Seeding and Planting Information for Asian Brassicas Planting dates Chinese broccoli Chinese cabbages Chinese mustards Daikon North Florida Aug - Feb Aug - Feb Aug - Feb Sept- Mar Central Florida Sept- Apr Sept- Apr Sept- Apr Sept- Apr South Florida Sept- Apr Sept- Apr Sept- Apr Sept- Apr Seeding information Number of rows/44-inch wide beds 3-4 2-3 4 3 (fall/spring) to (6 ft centers) 4 (winter) Distance between rows (in) 11 14 or 24 14 - mustard 11 11 – others (below) Distance between plants (in) 3-5 14-18 12-18 mustard 6-9 8-12 Shanghai/choy sum 6-10 baby bok choy 2 -4 u-choy Seeding depth (in) 0.25 – 0.5 0.25 – 0.5 0.25 – 0.5 0.25 Seed per acre (lb) Days to maturity from seed Plant populations (acre) 116,160 18,671 29,040 mustard 58,080 43,560 Shanghai/choy sum 58,080 baby bok choy 174,240 u-choy
Chapter 8: Production of Major Asian Vegetable in Florida Page 83Table 2a. Varieties and Trellising Requirements of Asian Cucurbits Crop Varieties Trellising Bittermelon – Chinese Chinese: Hong Kong Green, Hybrid Bangkok Large, Japan Green Sprinkle, Taiwan Large Yes Bittermelon - Indian Indian: Hybrid India Star NS, India Green Queen, India long Green Chayote (short lived perennial) The seed is the viviparous fruit itself. There is some debate as to whether varieties remain true Yes Fuzzy melon Chiang Shin Joker, Seven Star Long Yes Long gourd Hybrid India Long, Hybrid Asia Short Yes Angled luffa Hybrid Green Glory, Lucky Boy, Summer Long Yes Smooth luffa Smooth Beauty, Smooth Boy Yes Snake gourd Extra Long Dancer, Hybrid Snaky, Long EX Yes Winter melon Hybrid Asia Sweet, Hybrid Red Doll, Hybrid Wonder Wax NoTable 2b. Seeding, Planting Information for Asian Cucurbits Planting dates Bittermelon Long gourd Angled luffa Smooth luffa North Florida Feb – Apr; Feb – Apr; Feb – Apr; Feb – Apr; July – Aug July – Aug July – Aug July – Aug Central Florida Jan – Mar; Jan – Mar; Jan – Mar; Jan – Mar; Sept Sept Sept Sept South Florida Sept - Feb Sept - Feb Sept - Feb Sept - Feb Seeding information Distance between rows (in) 60 – 72 60 – 72 60 – 72 60 – 72 Distance between plants (in) 36 – 60 36 – 60 36 – 60 36 – 60 Seeding depth (in) Seed per acre Days to maturity from seed 80 – 100 Days to maturity from transplant Plant populations (acre) 2904 2904 2904 2904 Planting dates Fuzzy melon Snake gourd Chayote1 Winter melon North Florida Feb – Apr; Feb – Apr; Not recommended Feb 15 – Apr 15 July – Aug July – Aug Central Florida Jan – Mar; Jan – Mar; Not recommended Jan 15 – Mar 15 Sept Sept South Florida Sept - Feb Sept - Feb Sept - Feb Dec 15 – Mar 1 Seeding information Distance between rows (in) 60 – 72 60 – 72 60 – 72 72 – 108 Distance between plants (in) 36 – 60 36 – 60 36 – 60 36 – 72 Seeding depth (in) 1.5 – 2.0 1.5 – 2.0 Whole fruit is used – should 1.5 – 2.0 be covered half way Seed per acre 2904 – whole fruit Days to maturity from seed Days to maturity from transplant Plant populations (acre) 2904 2904 2904 1452-2420 1 hayote flowers and sets fruit under short day conditions and lives for a few years, so it is not recommended for areas where freezing temperatures are likely to occur on an C annual basis.
Page 84 Vegetable Production Handbook LEGUMES SOLANUMS The Asian legume group (Tables 3a and 3b) includes The Asian solanum group (Tables 4a and 4b) includesfruits (usually known as pods), which are eaten at the three types of eggplant and bird’s eye pepper. Pea eggplant,immature stage, crop with edible immature seeds (green which was discussed in previous editions of the Handbook,shell), and stem tips. The winged bean also has edible is on the Federal Noxious Weed list, so it has not includedleaves and roots, though the latter do not appear to be cul- here. The harvestable product includes fruits which aretivated commercially in the Continental U.S. All the pole eaten at the immature or mature stage. All can be grown onor indeterminate types can be grown on raised beds with- raised beds with or without plastic mulch and using eitherout mulch using drip, overhead or subsurface irrigation. drip or subsurface irrigation. As with most eggplants, theseFenugreek does not grow well in rocky soils, such as those types tend to be short-lived perennials, especially the Thaifound in Miami-Dade County. Pigeon peas are a semi- eggplant which is a relatively compact, stocky plant. Theyperennial shrub in warmer areas. Many pigeon pea and can be severely pruned and allowed to regrow if stakingwinged bean varieties are short day and only flower during does not prohibit this operation. Fertilizer recommenda-the fall. There are some day neutral varieties available of tions for eggplant should be used for the three types ofboth crops. Fertilizer recommendations for pole beans are eggplant, while those for peppers should be followed forgenerally applicable to this group. All of these crops are bird’s eye peppers (Table 4c). These crops can be startedstarted from seed, though winged beans require scarifica- from seed or transplants. All the indeterminate types needtion prior to planting. All the indeterminate types need some type of support.some type of support, ranging from individual bamboostakes to trellises. For pest control products, these crops are BOTANYincluded in Crop Group 6 (Legume Vegetables [Succulent Nomenclatureor Dried]), with the exception of pea shoots which are not Oriental eggplant, Japanese / Chinese -in a crop group at present. Solanum melongena BOTANY Thai eggplant – Solanum melongena Nomenclature Indian eggplant – Solanum melongena Cluster bean, Guar – Cyamopsis tetragonolobus Bird’s-eye pepper – Capsicum frutescens though some Edamame – Glycine max say perhaps C. chinense Fenugreek, methi – Trigonella foenum-gracum Hyacinth bean, lablab bean – Lablab purpureus SEED SOURCES(Dolichos lablab, D. nigar, Lablab vulgaris) Evergreen Seeds, Pigeon pea – Cajanus cajan http://www.evergreenseeds.com/ Snow / snap (edible podded) pea –Pisum sativum Johnny’s Selected Seed, http://www.johnnyseeds.com/ Winged bean – Psophocarpus tetragonolobus Kitazawa Seeds, Yard-long bean – Vigna unguiculata http://www.kitazawaseed.com/ Known-you Seed Company, Ltd., http://www.knownyou.com/ Redwood City Seed Company, http://www.ecoseeds.com/ Sakata, http://www.sakata.com/Catalog.aspx Takii Seeds, http://www.takii.com/
Chapter 8: Production of Major Asian Vegetable in Florida Page 85Table 3a. Names, Life Cycle, Varieties and Trellising Requirements of Asian Legumes Crop Life cycle Varieties Trellising Cluster bean, Guar Annual Yes Edamame Annual Green Legend, Lucky Lion No Fenugreek, methi Annual No Hyacinth bean, lablab bean Annual Asia Purple, Asia White No Pigeon pea (a short-lived perennial) Short-lived perennial No Snow / snap (edible podded) pea Annual Mammoth Melting Sugar, Dou Miao Yes Winged bean Annual Youdou Yes Yard-long bean Annual Orient Extra Long, Stickless Wonder YesTable 3b. Seeding, Planting and Maturity Information for Asian Legumes Planting dates Cluster bean Fenugreek Edamame Hyacinth bean North Florida Mar – Apr; Mar – Apr; Mar – Apr; Mar – Apr; Aug Aug Aug Aug Central Florida Feb – Mar; Feb – Mar; Feb – Mar; Feb – Mar; Aug – Sept Aug – Sept Aug – Sept Aug – Sept South Florida Sept - Apr Sept - Apr Sept - Apr Sept - Apr Seeding information Distance between rows (in) 24 9 20 - 24 20 Distance between plants (in) 6 2 – 3, thin to 4 (if only 2–6 4-6 growing a small amount) Seeding depth (in) 1 – 1.5 1 – 1.5 1 – 1.5 1 – 1.5 Seed per acre 43,560 348,480 156,820 78,409 Days to maturity from seed 90 – 120 Plant populations (acre) Planting dates Pigeon pea Snow / snap pea Winged bean Yard-long bean North Florida Jan – Mar Mar – July Central Florida Nov – Feb Feb – Aug South Florida Mar – Apr Nov – Feb Mar – Apr Sept - Apr Seeding information Distance between rows (in) 24 – 36 30 – 36 (hand harvest) 36 28 – 36 8 – 10 (machine harvest) Distance between plants (in) 24 – 36 1.2 – 2 8 2–4 Seeding depth (in) 1 – 1.5 1 – 1.5 1 – 1.5 1 – 1.5 Seed per acre Days to maturity from seed 180 (early varieties); 90 – if day neutral varieties 70 270 – 365 days (late varieties) are used; SD otherwise Plant populations (acre) 10,890 174,240 (hand) 21,7801 112,012
Page 86 Vegetable Production HandbookTable 4a. Names, Varieties and Trellising Requirements of Asian SolanumsCrop Varieties StakingOriental eggplant, Japanese / Chinese Japanese: Hybrid Mangan Yes Chinese: Hybrid Purple Charm, Ma-Zu PurpleThai eggplant – White: Hybrid White Ball Maybethis can be a short-lived perennial Green: Green Beauty Purple: Hybrid Violet Prince Variegated: Hybrid TigerIndian eggplant, dark & wine colored Hybrid Bharata Star, Hybrid Chu-Chu YesBird’s-eye pepper MaybeTable 4b. Seeding, Planting and Maturity Information for Asian Solanums EggplantPlanting dates Japanese/ Chinese Thai Indian Bird’s eye peperNorth Florida Feb – Mar Feb – Mar Feb – Mar Aug 15; Feb – MarCentral Florida Aug – Sept; Aug – Sept; Aug – Sept; Aug – Sept; Jan – Feb Jan – Feb Jan – Feb Jan – MarSouth Florida Aug - Feb Aug - Feb Aug - Feb Aug – FebSeeding informationDistance between rows (in) 36 – 72 36 – 72 36 – 72 36 – 48Distance between plants (in) 18 – 40 36 – 60 18 – 40 10 – 24Seeding depth (in) 0.5 – 0.75 0.5 – 0.75 0.5 – 0.75 0.5 – 0.75Seed per acre to transplant (lbs) 0.25 – 0.5 0.25 – 0.5 0.25 – 0.5 0.25 – 0.5Days to maturity from transplantPlant populations (acre) 9,680 9,680 4,840 17,500
Chapter 9. 2012-2013Cucurbit Production in FloridaS.M. Olson, P.J. Dittmar, P.D. Roberts, S.E. Webb and S.A. Smith BOTANY melon - 250 cwt. In most instances, however, harvested Nomenclature yield is usually much less than potential yield because of Family - Cucurbitaceae market constraints. Cucumber - Cucumis sativus Cantaloupe- Cucumis melo Disease Resistance: Varieties that combine disease Summer squash - Cucurbita pepo resistance with other desirable horticultural characteristics Pumpkin jack-o-lantern is C. pepo; some processing ( should be selected when possible. Most modern cucum- pumpkins are C. maxima and C. moschata) ber varieties are resistant or tolerant to angular leaf spot, Butternut squash - Cucurbita moschata anthracnose, downy mildew, powdery mildew, cucumber Tropical pumpkin (Calabaza) - Cucurbita moschata mosaic virus, and scab. Some cantaloupe varieties have Winter squash - ucurbita maxima e.g. hubbard, C tolerance to downy and powdery mildew, and fruit should buttercup, and Turk’s Turban be resistant to fruit rots. Unfortunately, disease tolerance Watermelon - Citrullus lanatus is limited in squash and pumpkin varieties at the pres- ent time. However, summer squash varieties resistant to Origin a number of diseases, including viruses, are available to Cucurbits originated in several different locations: growers in limited numbers. Watermelon varieties selectedcucumber (India); cantaloupe (Africa); summer squash for use in Florida should have resistance to anthracnose-(Mexico, Central America); butternut squash (Mexico, race 1 and fusarium wilt. There is considerable variationCentral America); winter squash (South America); and among varieties in the degree of fusarium resistance; selectwatermelon (Central Africa). varieties with high wilt resistance that have qualities com- patible with other requirements. Related Species Several Oriental and specialty vegetables, including Horticultural Quality: Slicing cucumber fruit shouldChinese winter melon, calabash gourd, luffa gourd, bitter be smooth and uniformly dark green, have an appropri-melon, and chayote are also included in the Cucurbitaceae ate length:diameter ratio, have small seeds that are slowfamily. to develop, and have a desirable flavor. Pickling cucum- ber fruit should be firm, medium to dark green in color, have a small seed cavity, an L/D ratio of about 3 at 11/4 in. diameter, and good brining qualities if it is to be brined. VARIETIES Gynoecious plants are preferred. Western-type cantaloupes Variety selection, often made several months before should be sutureless (smooth) or nearly so, round to slight-planting, is one of the most important management deci- ly oval, fully netted, and about 3 lb average weight with asions made by the grower. Failure to select the most suit- thick deep-salmon interior, and should have a small tightable variety or varieties may lead to loss of yield or market seed cavity, high soluble solids (11% is required for theacceptability. U.S. Fancy grade), and a pleasant aroma and taste. Eastern- type cantaloupes are sutured and have soft flesh. Desirable The following characteristics should be considered in traits in pumpkin varieties include a deep orange rind thatselection of vine crop varieties for use in Florida: colors early, smooth fruit, a stem that is proportional to the fruit size and adheres tightly to the fruit, and freedom from Yield: The variety selected should produce crops equiv- fruit rots. Summer squash fruit should have color appropri-alent to the best varieties available. In recent years, the ate to the market requirements, retain their gloss as theyaverage harvested yields per acre of vine crops in Florida mature, and be slow to develop seed. Winter squash fruithave been: fresh market cucumber - 525 bu, processing should be attractively colored; have a smooth, hard rind;cucumbers - 10 tons, cantaloupe -200 cwt, pumpkins - deep orange flesh; be resistant to storage rot; and have anexperimental yields average about 200 cwt, summer squash appropriate storage life. Watermelon fruit size and shape;- 300 bu, Tropical pumpkin (calabaza) 500 cwt, and water- rind color, thickness, and toughness; seed size, number, Page 87
Page 88 Vegetable Production Handbookand color; and flesh color, texture, and soluble solids (10%is required for designation as very good internal quality) Halloween Pumpkinare all important characteristics to be considered in selec- Miniature:< 1 lbtion of watermelon varieties. Ability to germinate in cold Bumpkin (H)soils and general plant vigor may be important in certain Gold Dust (H)situations. Jack-Be-Little Jack-Be-Quick Adaptability: Vine crops are well adapted to produc- Munchkintion in Florida for spring, early summer, and fall markets Wee-Be-Little (PVP)1and to the winter market in the very warmest growingareas. Successful varieties must perform well under the Small: 1-5 lbrange of environmental conditions encountered in these Baby Pamseasons and in various locations in Florida. Little Lantern Pick-A-Pie (H) Market Acceptability: For all vine crops, growers must Small Sugarbe aware of the needs of the particular market they intend Trickster (H)2to supply, and grow varieties that produce crops that satisfythat market. Medium: 5-10 lb Autumn Gold (H) Jack of All Trades (H) Magician (H) VINE CROP VARIETIES FOR FLORIDA Magic Lantern (H) Cucumber Merlin (H)Pickling: October (H) Calypso (H)1 (GY)2 Wizard (H) Excel (H) (GY) Eureka (H) (MO) Large: 10-20 lb FMX 5020 (H) Big Autumn (H) Jackson Classic (H) (GY) Connecticut Field Napoleon Classic (H) (MO) Gold Medal (H) Royal (H) (GY) Jumpin Jack Transamerica (H) ProGold 510 (H)Slicing: Giant: 25-80 lb Cobra (H) (GY) Prizewinner (H) Darlington (H) (GY) Dasher II (H) (GY) 1(PVP=Plant Variety Protection) Daytona (H) (GY) 2(H=hybrid) Dominator (H) (GY) General Lee (H) (GY) Impact (H) (GY) Indy (H) (GY) Lightning (H) (GY) Speedway (H) (GY) Thunder(H) (GY)1(H=hybrid)2(Flower Habit - GY=gynoecious,MO=monoecious) Cantaloupe Athena (H) Carribean Gold Eclipse (H) Odyssey (H) Vienna (H)1(H=hybrid)
Page 90 Vegetable Production Handbook SEEDING AND PLANTING and the diploid is the male or pollen parent (Diagram 1). Since the tetraploid seed parent produces only 5 to 10% as Planting dates and seeding information for cucurbits are many seeds as a normal diploid plant, seed cost is consid-given in Table 1. erably more than that of diploid, open-pollinated varieties and higher than diploid watermelon varieties. Tetraploid lines are usually developed by treating diploid plants with a chemical called colchicine. TRIPLOID WATERMELON PRODUCTION Fruit of diploid watermelon varieties may contain asmany as 1,000 seeds in each fruit. The presence of seedsthroughout the flesh makes the removal of seeds while eat-ing difficult. The seeds in slices or chunks of watermelonsold in retail stores or salad bars are a nuisance. One rea-son that seedless grapes are more popular with consumersthan seeded varieties is that the consumer does not have tobe concerned with and inconvenienced by the seeds whilethe fruit is being eaten. With proper care, seedless water-melons have a longer shelf life than seeded melons. Thismay be due to the fact that flesh break down occurs in thevicinity of seeds, which are absent, in seedless melons. Hybrid triploid (seedless) watermelons have been grownfor over 40 years in the United States. However, it was notuntil recently that improved varieties, aggressive market-ing, and increased consumer demand created a rapidlyexpanding market for triploid watermelons. The seed-less condition is actually sterility resulting from a cross Diagram 1. Steps involved in triploid watermelon seed production. Tobetween two plants of incompatible chromosome comple- produce seed, a diploid (2N) female parent plant is treated with colchicine to produce the solid-colored female tetraploidments. The normal chromosome number in most living (4N) parent; this is crossed with a striped male parent (2N)organisms is referred to as 2N. Triploid watermelons are which results in triploid (triploid) watermelon seed (3N). Toproduced on highly sterile triploid (3N) plants which result produce a crop of triploid watermelons, the 3N seed is inter-from crossing a normal diploid (2N) plant with a tetraploid planted with a 2N pollenizer variety.(4N). The tetraploid is used as the female or seed parentTable 1. Seeding and planting information for cucurbits. Planting dates Cucumber Cantaloupe Pumpkin1 Squash2 Watermelon North Florida Feb - Apr; July - Aug Feb 15 - Apr 15 Early July Feb - Apr; Aug - Sept 15 Feb 15 -Apr 15 Central Florida Jan - Mar; Sept Jan 15 - Mar 15 Mid July Jan - Apr; Aug - Sept Jan 15 - Mar 15 South Florida Sept - Feb Dec 15 - Mar 1 Early August Aug - Mar Dec 15 - Mar 1 Seeding information Bush Vining Distance between rows3 (in) 48 - 60 60 - 72 60 - 108 36 - 48 60 - 108 60 - 108 Distance between plants (in) 6 - 12 24 - 36 36 - 60 12 - 24 36 - 60 24 - 72 Seeding depth (in) 0.5 - 0.75 0.5 - 1.0 1.5 - 2.0 1.0 - 1.5 1.5 - 2.0 1.5 - 2.0 Seed per acre (lb) 2-4 1-2 4-5 2-3 1 - 1.5 1-3 Days to maturity from seed 40 - 65 85 - 110 80 - 100 40 - 50 85 - 120 80 - 100 Days to maturity Not 70 - 90 70 - 90 Not Not 60 - 90 from transplant recommended recommended recommended Plant populations4 (acre) 21,780 4,356 2,904 14,520 2,904 4,356 1 For Halloween market, for tropical pumpkin follow planting dates for squash. 2 For vining types in fall, plant during July same as pumpkins 3 ucumber and squash can be grown in two rows per bed (especially mulch culture) with 12 to 18 inches between rows on the bed (Fig. 9-5). C 4 Populations based on closest between and within row spacing.
Chapter 9: Cucurbit Production in Florida Page 91 Tetraploid parental lines normally have a light, medium, Field Arrangementor dark green rind without stripes. By contrast, the diploid There are two methods that can be used to incorporatepollen parent almost always has a fruit with a striped rind. pollenizer plants into the field. Dedicated row pollenizerThe resulting hybrid triploid melon will inherit a striped plantings place the pollenizer variety in the outside rowpattern. Growers may occasionally find a non-striped fruit and then every third row. An alternative is to plant the pol-in fields of striped triploid watermelons. These are the lenizer between every third and fourth plant in-row withoutresult of accidental self pollinations of the tetraploid seed changing plant spacing. When this latter method is chosen,parent during triploid seed production. Tetraploid fruit are the use of a special pollenizer is recommended. The useof high quality but will have seeds and must not be sold as of standard diploid varieties planted in-row may decreaseseedless. The amount of tetraploid contamination is depen- yields of closely associated triploid plants. Special pol-dent upon methods and care employed in triploid seed lenizer varieties have been developed solely for pollenproduction. production and most do not produce marketable fruit. The use of special pollenizers planted in-row allows the field Sterile triploid plants normally do not produce viable to be 100% seedless. Special pollenizer varieties found toseed. However, small, white rudimentary seeds or seed- perform well in Florida are listed below.coats, which are eaten along with the fruit as in cucumber,develop within the fruit. The number and size of these Triploid Watermelon Pollenizersrudimentary seeds vary with variety. An occasional dark, Ace Pollen Pro1hard, viable seed is found in triploid melons. Jenny Sidekick Patron SP-41 Triploid watermelons can be grown successfully inareas where conventional seeded varieties are produced. Pinnacle SP-51However, they require some very unique cultural practices Polimaxfor successful production. 1 Resistant to 1 or more races of Fusarium wilt Stand Establishment Containerized production of triploid watermelon When using pollenizer plants arranged in dedicatedtransplants is essential because of the special conditions rows, it is important to use a pollenizer variety that is mar-required for seed germination, emergence, and early ketable because up to one-third of all melons produced inplant development not found in open-field situations. the field will be of this variety.Furthermore, the extra cost of seedling production is justi-fied because triploid watermelon seeds costs are about When dedicated rows are used, special pollenizer plantssix times greater than those of diploid hybrid seeds and should be transplanted at the same times as triploid plants.60 times greater than open-pollinated diploid watermelonseeds. One seed per cell should be planted 1 inch deep Cultural Practiceswith the radicle (pointed end) up to reduce seedcoat adher- Plant spacing requirements vary depending on varietyence to the cotyledons. Transplants have been successfully selection, growing area, time of planting, and soil type. Inproduced with peat pellets or in trays containing sterile general, early growth of triploid plants is slower than thatmedia with 1 to 2 inch cell size. The tray is watered lightly of diploid plants. However, triploid plant size eventuallyto bring the seed and mix in contact. Stacked trays are exceeds that of diploid plants. Seed development in fruitplaced in a germination chamber 85-90˚F for two days or of diploid varieties inhibits further flowering and fruit set.until radicles are visible in the cell drainage holes. The This inhibition does not exist in triploids; therefore, plantstrays are then arranged in a greenhouse with day tem- continue to produce fruit as long as viral infection does notperature 70-80˚F and night temperature 65-70˚F where occur, insects and foliar diseases are controlled and envi-temperature control can be achieved. Plants are fertilized ronmental conditions are favorable. Triploid plant popula-every three days with a solution containing 50 ppm N from tion density may be 10 to 20% less than that recommendedCa(NO3)2 and KNO3 from cotyledon expansion until the for production of diploid watermelon varieties. Triploidfirst true leaf is fully expanded, then with a 200 ppm N watermelon production has been successful with 25-30 sq.solution applied every other day until the second true leaf ft. per plant.is fully expanded, finally the fertilizer is reduced for sev-eral days before transplanting to the field. Plants are ready All methods of irrigation including overhead, drip, seep-for transplanting when the roots are sufficiently developed age, and furrow are used successfully in producing triploidto permit removal from the cell with the entire growing watermelons. Maintaining soil moisture at optimum levelsmix volume intact. This will require three to five weeks is critical for triploid watermelon production. Water stressdepending on cell size and growing conditions. (drought) can increase the incidence of blossom-end rot
Page 92 Vegetable Production Handbookand result in poorly shaped, bottle-neck fruit. Excessive IRRIGATIONfield moisture has been associated with hollowheart, a dis-order which seems to be more severe in some varieties of Cucurbit water requirements are slightly lower thantriploid melons than in diploid varieties. those of other vegetable crops. Peak water requirements during rapid growth and development may average 90% of reference evapotranspiration levels (ETo), decreas- ing to 70% of ETo during the final growth period (Tables FERTILIZER AND LIME 3 to 6, Chapter 3, Principles and Practices of Irrigation For unmulched crops, incorporate all P2O5, micronutri- Management for Vegetables). Many of these crops haveents, and 25 to 50% of N and K2O in the bed area. Apply extensive root systems and can obtain available groundno more than 25% N and K2O broadcast for subsurface moisture, thus reducing irrigation requirements. It is impor-irrigated crops. This “modified broadcast” method improves tant to note that excessive irrigation can reduce crop yieldsfertilizer efficiency. Apply remaining N and K2O as a sid- by leaching crop nutrients or promoting disease. However,edressing when squash has four to six true leaves or when plant stress from limited water availability will also reducevines begin to run. fruit size and quality. For mulched crops under subsurface irrigation, broad-cast all P2O5, micronutrients, and 20 to 25% of N and K2O POLLINATION OF CUCURBITSin the bed area. Apply remaining N and K2O in bands ingrooves (2 to 3 inches deep) and 8 to 10 inches from row. Cucurbit plants have separate male (staminate) andUse a single band in bed center for twin-row crops and two female (pistillate) flowers. Male flowers generally appearshoulder bands for single-row crops. on the plants several days before female flowers. The female flower is easily recognized by the presence of a For mulched crops with sprinkler irrigation, incorporate miniature fruit below the flower petals. Pollen from theall fertilizer in bed before mulching. Cover with unfertilized male flower must be transferred to the female flower forsoil so fertilized soil is likely to remain moist. Plastic mulch pollination and subsequent fruit development to occur.might need to be perforated to provide irrigation infiltrationon deep, droughty sands. Supplemental N and K2O can be Therefore, it appears that a sufficiently high honey- beeapplied by liquid fertilizer injection wheel. population is necessary to insure that each flower is visited at least eight times. How does this translate into hives per For drip irrigated crops, broadcast all P2O5, micronutri- acre? Recommendations from various sources range froments, and up to 20 to 25% of N and K2O in the bed. Apply two hives per acre to one hive per 5 acres. Under most con-remaining N and K2O through the irrigation tube. ditions, however, one strong hive per 2 acres should result in sufficient bee activity to effect needed pollination. Soil test and fertilizer recommendations for cucurbits onmineral soils are given in Table 2. An injection schedule for Cucurbit flowers open shortly after sunrise and remainN and K for cucurbits grown on soils testing very low in K open until late afternoon or early evening. Accordingly,is given in Table 3a and 3b. each flower is open for only a few hours. The period of maximum honeybee - the most common and effective polli- nator of cucurbits - activity closely coincides with the peri- od when the flower is open. Honeybee visitation begins an PLANT TISSUE ANALYSIS hour or two after sunrise and continues until mid-afternoon. Plant tissue analysis information for cucurbits is given If temperatures are very warm, bee activity may declinein Table 4. The analysis was done at the early bloom stage, about noon. Research on cantaloupe pollination conductedusing the most recently matured leaf. in California showed that bee visitations increased until 10 a.m. and then declined until 3 p.m. when activity almost ceased. PETIOLE SAP TESTING Research on watermelon showed that the number of bee visitations was more important than the length of time that Fresh sap can be pressed from leaf petioles and analyzed each bee stayed on the flower. Well-shaped, fully expandedfor nitrogen and potassium concentrations. Results can fruit occurred following eight bee visitations to a femalebe used to make adjustments in the fertilization program. flower. Fruit set was significantly reduced when only fourSufficiency ranges for sap testing for cucurbit crops are pre- or two bee visitations were made. Hives should be spacedsented in Table 5. around the perimeter of large fields to provide distribution
Chapter 9: Cucurbit Production in Florida Page 93 Table 2. Soil test and fertilizer recommendations for cucurbits on mineral soils.1 VL L M H VH VL L M H VH P2O53 K2O3 BedTarget pH spacing (ft) N lb/A3 (lb/A/crop season)Cucumber6.5 6 150 120 100 80 0 0 120 100 80 0 0Muskmelon6.5 5 150 150 120 100 0 0 150 120 100 0 0Pumpkin6.5 8 150 120 100 80 0 0 120 100 80 0 0Squash26.5 6 150 120 100 80 0 0 120 100 80 0 0Watermelon6.0 8 150 150 120 100 0 0 150 120 100 0 01 See Chapter 2 section on supplemental fertilizer application and best management practices, pg 11.2 Summer and winter3 eeds and transplants may benefit from applications of a starter solution at a rate no greater than 10 to 15 lbs/acre for N and P O , and applied through the plant hole or near S 2 5 the seeds. Table 3a. Injection schedule for N and K for cucurbit crops grown on soils testing very low in K. Total nutrients (lb/A) Crop development Injection (lb/A/day)1 Bed Crop spacing (ft) N K2O Stage Weeks 2 N K2OCucumber 6 150 120 1 1 1.0 1.0 2 2 2.0 1.5 3 6 2.5 2.0 4 1 2.0 1.5Muskmelon 5 150 150 1 2 1.0 1.0 2 3 2.0 2.0 3 3 2.5 2.5 4 2 2.0 2.0 5 2 1.0 1.0Squash 6 150 120 1 2 1.5 1.0 2 5 2.5 2.0 3 4 1.5 1.5Watermelon 8 150 150 1 2 1.0 1.0 2 2 1.5 1.5 3 4 2.5 2.5 4 3 1.5 1.5 5 2 1.0 1.01 ll nutrients injected. Actual amounts may be lower depending on amount of N and K O placed in the bed and the K soil test result. A 22 tarting from date of seedling emergence or transplanting. First two weeks worth of injecting can be omitted if 25% of total N and K O was applied preplant. S 2
Page 94 Vegetable Production Handbookof bees over the entire field. To maintain the health and INSECT MANAGEMENTactivity of the bee colonies, pesticide applications to thecrop should be made when bees are not present in the field, Insecticides approved for use on cucurbit crops are out-usually at dusk or after dark. lined in Table 8. WEED MANAGEMENT PRODUCTION COSTS Herbicides labeled for weed control in cucurbit crops Example breakeven production costs for cucurbitsare listed in Table 6. grown in Florida are given in Tables 9, 10, 11, and 12. DISEASE MANAGEMENT Chemicals approved for disease management in cucur-bits are listed in Table 7. Table 3b. upplemental fertilization recommendations for cucurbit crops grown in Florida on sandy soils testing very low in Mehlich-1 S potassium (K20). Recommended-Supplemental fertilizationz Production Measured "low" plant System Nutrient Leaching raint,u nutrient content x.w.u Extended harvest season x.u Plasticulture N n/a 1.5 to 2 lbs/A/day for 7 daysy 1.5 to 2 lbs/A/day y, v K2O n/a 1.5 to 2 lbs/A/day for 7 daysy 1.5 to 2 lbs/A/day y, v Bare ground N 30 lbs/As 30 lbs/As 30 lbs/A v K2O 20 lbs/As 20 lbs/As 20 lbs/A v z A = 7,260 linear bed feet per acre (6-ft bed spacing); for soils testing "very low" in Mehlich 1 potassium (K O) 1 2 y ertilizer injections may be done daily or weekly. Inject fertilizer at the end of the irrigation event and allow enough time for proper flushing afterwards. F x lant nutritional status may be determined with tissue analysis or fresh petiole-sap testing, or any other calibrated method. The "low" diagnosis needs to be based on UF/IFAS P interpretative thresholds. w lant nutritional status must be diagnosed every week to repeat supplemental application. P v lant nutritional status must be diagnosed after each harvest before repeating supplemental fertilizer application. P u upplemental fertilizer applications are allowed when irrigation is scheduled following a recommended method (see Chapter 3 on irrigation scheduling in Florida). Supplemental S fertilization is to be applied in addition to base fertilization when appropriate. Supplemental fertilization is not to be applied "in advance with the preplant fertilizer. t leaching rain is defined as a rainfall amount of 3 inches in 3 days or 4 inches in 7 days. A s upplemental amount for each leaching rain. S
Chapter 9: Cucurbit Production in Florida Page 95 Table 4. Plant tissue analysis at early bloom stage for cucurbits. Dry weight basis. N P K Ca Mg S Fe Mn Zn B Cu Mo Status Percent Parts per million Cucumber Deficient <2.5 0.25 1.6 1.0 0.3 0.3 40 30 20 20 5 0.2 Adequate range 2.5 -5.0 0.25 -0.6 1.6 -3.0 1.0 -3.5 0.3 -0.6 0.3 -0.8 40 -100 30 -100 20 -50 20 -60 5 -10 0.3 -1.0 High >5.0 0.6 3.0 3.5 0.6 0.8 100 100 50 60 20 2.0 Toxic (>) 900 950 150 Cantaloupe Deficient <4.0 0.4 5.0 1.0 0.35 0.2 40 20 20 20 5 0.6 Adequate range 4.0 -5.0 0.4 -0.7 5.0 -7.0 1.0 -2.0 0.35 -0.45 0.2 -0.8 40 -100 20 -100 20 -60 20 -80 5 -10 0.6 -1.0 High >5.0 0.7 7.0 2.0 0.45 0.8 100 100 60 80 10 1.0 Toxic (>) 900 150 Pumpkin Deficient <3.0 0.3 2.3 0.9 0.35 0.2 40 40 20 25 5 0.3 Adequate range 3.0 -6.0 0.3 -0.5 2.3 -4.0 0.9 -1.5 0.35 -0.60 0.2 -0.4 40 -100 40 -100 20 -50 25 -40 5 -10 0.3 -0.5 High >6.0 0.5 4.0 1.5 0.6 0.4 100 100 50 40 10 0.5 Summer Squash Deficient <3.0 0.25 2.0 1.0 0.3 0.2 40 40 20 25 5 0.3 Adequate range 3.0 -5.0 0.25 -0.5 2.0 -3.0 1.0 -2.0 0.3 -0.5 0.2 -0.5 40 -100 40 -100 20 -50 25 -40 5 -20 0.3 -0.5 High >5.0 0.5 3.0 2.0 0.5 0.5 100 100 50 40 20 0.5 Watermelon Deficient <2.5 0.25 2.7 1.0 0.25 0.2 30 20 20 20 5 0.3 Adequate range 2.5 -3.5 0.25 -0.50 2.7 -3.5 1.0 -2.0 0.25 -0.50 0.2 -0.4 30 -100 20 -100 20 -40 20 -40 5 -10 0.3 -0.5 High >3.5 0.5 3.5 2.0 0.5 0.4 100 100 40 40 10 0.5 Table 5. Sufficiency ranges for petiole sap testing for cucurbits. Fresh petiole sap concentration (ppm) Fresh petiole sap concentration (ppm) Crop Crop development stage NO3-N K development stage NO3-N K Cucumber Squash First blossom 800-1000 NR1 First blossom 900-1000 NR1 Fruit three-inches long 600-800 First harvest 800-900 First harvest 400-600 Cantaloupe Watermelon First blossom 1000-1200 3000-32001 Vines 6" in length 1200-1500 4000-5000 Fruits two-inches long 800-1000 — Fruits 2" in length 1000-1200 4000-5000 First harvest 700-800 — Fruits one-half mature 800-1000 3500-4000 At first harvest 600-800 3000-3500 1 NR-No recommended ranges have been developed.
Page 96 Vegetable Production HandbookTable 6. Chemical weed control in cucurbits.Active ingredient Trade namelb. ai/A Product/A Crops Weeds Controlled / Remarks***PRETRANSPLANT AND PREEMERGENCE***Bensulide (Prefar) 4E All cucurbits Annual broadleaf and grass control. Incorporate or irrigate 1 to 2 5 to 6 5 – 6 qts. inches within 36 hrs. of application. Nonlabeled crops should not be planted within 120 days of application.Carfentrazone (Aim) 2 EC All cucurbits Emerged broadleaf control. Post-direct hooded application to row up to 0.031 up to 2 fl. oz. middles for burndown of emerged broadleaf weeds. Use crop oil concentrate or nonionic surfactant at recommended rates. mineral and muck soilClomazone (Command) 4ME Cucumber Annual broadleaf and grass control. Use lower rates in coarse 0.15 – 0.38 0.4 to 1 pt. soils.Clomazone (Command) 4ME Melons (Muskmelon, Annual broadleaf and grass control. Use lower rates in coarse 0.15 – 0.25 0.4 – 0.67 pt. Watermelon) soils.Clomazone (Command) 4ME Summer & Winter Annual broadleaf and grass control. Use lower rates in coarse 0.25 – 0.5 0.67 – 1.33 pt. Squash soils. Consult label for cultivars where application is prohibited. Do not apply under plastic, apply only between plasitic covered beds.Ethalfluralin + (Strategy) Cucumbers, Melons, Annual broadleaf and grass control. Must be applied no laterClomazone 2 – 3 pt. Summer & Winter than 2 days after seeding. Overhead irrigation or rainfall of 0.5 Squash, Pumpkin, inch within 5 days. Do not apply under row mulch or over top of Watermelon plants.Flumioxazin (Chateau) 51 WDG Cucumber, Broadleaf control. Row middles only. Do not apply after crops are up to 0.125 up to 4 oz Muskmelon, transplanted / seeded. Raised plastic beds must be at least 4 in. Watermelon, higher than treated row middle and 24-in. wide bed. All applications Pumpkins, Summer & must be made with shielded or hooded equipment. Label is a Third- Winter Squash Party registration (TPR,Inc). Use without a signed authorization and waiver of liability is a misuse of the product.Glyphosate (various formulations) All cucurbits Control emerged broadleaf and grass weeds. Consult individual 0.3 – 1.0 labels for restrictions.Halosulfuron (Profine, Sandea) 75 DG Cantaloupe, Cucumber, Yellow and purple nutsedge and broadleaf control. Apply uniform- 0.024 0.5 oz Crenshaw, Honeydew ly with ground equipment in a minimum of 15 gallons of water/A.Halosulfuron (Profine, Sandea) 75 DG Watermelon Yellow and purple nutsedge and broadleaf control. May be applied 0.024 – 0.036 0.5 - 0.75 oz. preemergence to seeded watermelon on bareground or pre-seed- ing to mulch-cultured watermelon. Transplanting should be no sooner than 7 days after application. Use lighter rates on sandy soils with low organic matter.Halosulfuron (Profine, Sandea) 75 DG Pumpkins, Winter Yellow and purple nutsedge and broadleaf control. Apply before 0.024 – 0.036 0.5 – 0.75 oz. squash soil cracking or pre-transplant. Transplanting should not be made sooner than 7 days after application. May be applied post over- the-top when plants reach the 4-5 true leaf stage, but before first female flowers appear.Paraquat (Gramoxone Inteon) 2 SL Cucumber, Muskmelon, Controls emerged weeds. Apply prior, during, or after planting,0.63 to 0.94 Cantaloupe, Pumpkin, but before crop emerges. Use a non-ionic surfactant. Squash, WatermelonPelargonic acid (Scythe) 4.2 EC All cucurbits Controls emerged weeds. Apply before emergence of crop.3 – 10% Product is a contact, nonselective, foliar applied herbicide. There is no residual activity. May be tank mixed with soil residual com- pounds.S-metolachlor (Brawl, Dual Magnum) Pumpkin Annual broadleaf and grass weeds and nutsedge control. Apply0.95 – 1.26 1.0 – 1.33 as inter-row or inter-hill application. Leave a 1 foot untreated area over the seeded row (6 inches on either side of the row.) Use lower rates on lighter soils. Apply before weeds emerge.Terbacil (Sinbar) 80 WP Watermelon Annual broadleaf weed. Direct seeded: broadcast application after0.1 – 0.2 2 – 4 oz. seeding and before crop emergence. Transplanted: Sinbar can be applied under plastic mulch and row middles before transplanting. PHI 70 days.
Chapter 9: Cucurbit Production in Florida Page 97Table 6. Continued.Active ingredient Trade namelb. ai/A Product/A Crops Weeds Controlled / Remarks***POSTEMERGENCE***Carfentrazone (Aim) 2 EC All cucurbits Emerged broadleaf control. Post-direct hooded application to row up to 0.031 up to 2 fl. oz. middles for burndown of emerged broadleaf weeds. Use crop oil concentrate or nonionic surfactant at recommended rates. PHI 0 mineral and muck soil days.Clethodim (Arrow, Intensity, Select) 2 EC Cucumber, squash, Annual and perennial grass control. Use a crop oil concentrate at- 0.125 6 to 8 fl. oz. melons, and all com- 1% v/v spray volume. Use nonionic surfactant in Select Max. PHI modities in crop group 14 days. (Select Max) 1 EC 0.07 - 0.125 9 to 16 fl. oz.DCPA (Dacthal) W75 Muskmelon, Annual grasses and certain broadleaf control. Apply only when 6 to 14 lbs. Cantaloupe, plants have 4-5 true leaves, are well-established, and growing Honeydew, conditions are favorable for good plant growth. Cultivate prior to (Dacthal) 6F Watermelon application to control emerged weeds.Ethalfluralin + (Strategy) Cucumbers, Melons, Annual broadleaf and grass control. After transplanting apply toClomazone 2 – 3 pt. Summer & Winter row middles only. Does not control emerged weeds. Squash, Pumpkin, WatermelonGlyphosate (various formulations) All cucurbits Control emerged broadleaf and grass weeds. Apply to row mid- 0.3 – 1.0 dles only. Consult individual labels for restrictions.S-metolachlor (Brawl, Dual Magnum) 7.62 EC Pumpkin Annual broadleaf and grass weeds and nutsedge control. Apply0.95 – 1.26 1.0 – 1.33 pt. as inter-row or inter-hill application. Leave a 1 foot untreated area over the plant (6 inches on either side of the row.) Use lower rates on lighter soils. Apply before weeds emerge. PHI 30 days.Paraquat (Gramoxone Inteon) 2 SL Cucumber, Muskmelon, Controls emerged weeds. Row middles only. Limit of 3 applica- 0.47 – 0.93 1.88 to 3.72 pt. Cantaloupe, Pumpkin, tions per year. Squash, Watermelon (Firestorm) 3 SL 1.25 – 2.48 pt.Pelargonic acid (Scythe) 4.2 EC Cucumber, Gourd, Controls emerged weeds. Row middles only. Use a shielded3 – 10% Muskmelon, sprayer directed to the row middles to reduce drift to the crop. Cantaloupe, Pumpkin, Squash, WatermelonSethoxydim (Poast) 1.5 EC All cucurbits Growing grass weeds. Include a crop oil concentrate. Efficacy0.19 – 0.28 1.0 – 1.5 pt. is decreased if weeds are under stress. Use 1 pt. for seedling grasses and 1.5 pt. on perennial grasses. PHI 14 days.Terbacil (Sinbar) 80 WP Watermelon Annual broadleaf weed. Apply to row middles only. Do not allow0.1 – 0.2 2 – 4 oz. contact with plant foliage. Do not exceed 4 oz. per year. PHI 70 days.
Page 98 Vegetable Production HandbookTable 7. Cucurbit fungicides and other disease management products. Max Rate/Acre Minimum Days toFungicide Chemical Pertinent DiseasesGroup (active ingredients) Applic. Season Harvest Reentry or Pathogens RemarksBe sure to read a current label before applying any chemical.M1 Badge SC, Badge X2, SEE INDIVIDUAL 1 Varies by Bacterial diseases (See See label Basic Copper 53, Champ LABELS product individual labels) DP Dry Prill, Champ from 4 hrs Formula 2 FL, Champ to 2 days WG, Champion WP, COC WDG, Copper-Count-N, Cueva, Cuprofix Ultra 40 Disperss, Cuprofix MZ Disperss, Kentan DF, Kocide 2000, Kocide 3000, Kocide DF, Nordox 75WG, Nu-Cop 3L, Nu-Cop 50WP, Nu-Cop 50DF, (Various copper formula- tions)M1 & M3 ManKocide 61.1DF 2.5 lb 128 lb 5 2 Alternaria leaf spot Labeled on cucumber, (Copper hydroxide & melons, and summer Mancozeb) Anthracnose squash. Not all diseases labeled for every crop. Bacterial fruit blotch See label. Cercospora leaf spot Downy mildew Gummy stem blightM2 (sulfur) SEE INDIVIDUAL 1 Powdery mildew See individual label. Do Many brands available: LABELS not use when tempera- tures are greater than 90M2 Cosavet DF, Kumulus DF, F or on sulfur-sensitive Micro Sulf, Microthiol various. Labeled for all Disperss, Sulfur 90W cucurbits.M3 Maneb 75 DF SEE INDIVIDUAL 5 1 Anthracnose Limit is 7 appl/crop. Do Maneb 80WP LABELS Alternaria leaf spot not tank mix with cop- per fungicides. Some Manex Cercospora leaf spot cantaloupe varieties may (maneb) Downy mildew be sensitive to EBCD products, check label or Gummy stem blight Extension resources for this informationM3 (mancozeb) SEE INDIVIDUAL 5 1 Alternaria leaf spot Labeled for all cucurbits. LABELS See inidividual labels. Many brands available: Anthracnose Dithane DF Rainshield, Cercospora leaf spot Dithane F45 Rainshield, Downy mildew Dithane M45, Manzate Pro-Stick, Penncozeb Gummy stem blight 4FL, Penncozeb 75DF, Penncozeb 80WP
Chapter 9: Cucurbit Production in Florida Page 99Table 7. Continued. Max Rate/Acre Minimum Days toFungicide Chemical Pertinent DiseasesGroup (active ingredients) Applic. Season Harvest Reentry or Pathogens Remarks M5 (Chlorothalonil) SEE INDIVIDUAL 0 1 Alternaria leaf spot Labeled for all cucurbits. Many brands available: LABELS Anthracnose Recommended maxi- mum rate is less for cer- Bravo Ultrex, Bravo Cercospora leaf spot tain diseases including Weather Stik, Bravo Downy mildew downy mildew. Follow ZN, Choloronil 720, label recommendations Chlorothalonil 720SC, Gummy stem blight on watermelon after Echo 720, Echo 90DF, Powdery mildew fruit set. Do not apply Echo ZN, Eqyys 500 ZN, to mature watermelons Equus DF, Equus 720 SST, under dry, hot and other Initiate 720, Initiate ZN environmental conditions listed on label.1 Topsin M 70WSP Topsin SEE INDIVIDUAL 1 1 Anthracnose Follow resistance man- 4.5FL LABELS agement guidelines on Topsin M WSB Powdery mildew label. Labeled for all cucurbits. Thiophanate methyl Gummy stem blight 85WDG T-methyl E-Ag 70WSB Target spot (Thiophanate-methyl) 3 Rally 40WSP 5 oz 1.5 lb 0 1 Powdery mildew Note that a 30 day plant Sonoma 40WSP back restriction exists. Follow resistance man- (Myclobutanil) agement guidelines on label. Labeled for all cucurbits.3 Folicur 3.6G 8 fl oz 24 fl oz 7 0.5 Powdery mildew Maximum rate is lower Monsoon 3.6G Gummy stem blight for powdery mildew. Gummy stem blight Orius 3.6F suppression is only for Tebustar 3.6L watermelon, squash, pumpkin, and melons. Teledo See label for individual Tebuzol 3.6F brands. (Tebuconazole) 3 Procure 50WS and 480SC 8 oz 40 oz 0 0.5 Powdery mildew Follow résistance man- (Triflumizole) agement guidelines on label. Labeled for all cucurbits.4 Apron XL SEE INDIVIDUAL 28 2 Damping off caused by Apply at seeding in a Ridomil Gold SL LABELS Pythium spp. 7-12” band on soil over seed furrow. Some must Ultra Flourish be applied with other (mefenoxam) fungicide. Labeled for all cucurbits. Allegiance FL Metastar 2E (metalaxyl) 4 & M1 Ridomil Gold/Copper 2 lb 8 lb 5 2 Downy mildew Limit is 4 appl/crop 64.8 W (mefenoxam & copper hydroxide)4 & M3 Ridomil Gold MZ WG 2.5 lb 10 lb 5 2 Downy mildew Limit is 4 appl./crop. (Mancozeb & Mefenoxam) Labeled for cucumbers, cantaloupe, melons, watermelon and summer squash.
Page 100 Vegetable Production HandbookTable 7. Continued. Max Rate/Acre Minimum Days toFungicide Chemical Pertinent DiseasesGroup (active ingredients) Applic. Season Harvest Reentry or Pathogens Remarks 4 & M5 Ridomil Gold Bravo SC 3.35 pt See label 7 2 Downy mildew Limit is 4 appl/crop. (mefenoxam & chloro- Certain leaf spots Rate for downy mildew thalonil) is lower. Labeled for all Gummy stem blight cucurbits.7 Endura 6.5 oz 26 oz 0 0.5 Alternaria blight Labeled for all cucurbits. (boscalid) Gummy stem blight Do not make more than one application of Endura Powdery mildew (sup- before alternating to pression) another labeled fungicide with a different mode of action for at least one application.7 & 11 Pristine 38WG 18.5 oz 74 oz 0 0.5 Downy mildew Labeled for all cucurbits. (boscalid &pyraclos- Alternaria leaf blight Limit is 4 appl/crop & trobin) Cercospora leaf spot alternate chemistry. Gummy stem blight Powdery mildew Anthracnose9&3 Inspire Super 20 fl oz 80 fl oz 7 Anthracnose Labeled for all cucurbits. (cyprodinil; difenocon- Alternaria leaf blight Do not make more than azole) two consecutive applica- Cercospora tions. Gummy stem blight Powdery mildew9 & 12 Switch 62.5WG 14 oz. See label 1 0.5 Alternaria leaf spot Labeled for all cucurbits. (Cyprodinal & Fludioxonil) and remarks Gummy stem blight Do not apply more than 56 oz/A per plot of land Powdery mildew per year. Do not make more than two consecu- tive applications before switching to fungicide with a different mode of action.11 Cabrio 20EG 16 fl oz 64 fl oz 0 0.5 Downy mildew 4 appl maximum. (Pyraclostrobin) Powdery mildew Maximum rate is less for downy mildew. Labeled Gummy stem blight for all cucurbits. Anthracnose Alternaria blight Certain leaf spots 11 Flint 50WP 2 oz 8 oz 0 0.5 Powdery mildew Limit is 4 appl/crop & (Trifloxystrobin) Downy mildew alternate chemistry. Maximum rate is higher for downy mildew sup- pression. Labeled for all cucurbits. 11 Heritage 8 oz 3 lb 1 4 hrs Anthracnose Do not make more than (Azoxystrobin) Belly rot two consecutive appli- cations. Do not make Downy mildew more than 6 appl/crop. Gummy stem blight See label for tank mixing restrictions. Labeled for Leaf spots- various all cucurbits. Powdery mildew
Chapter 9: Cucurbit Production in Florida Page 101Table 7. Continued. Max Rate/Acre Minimum Days toFungicide Chemical Pertinent DiseasesGroup (active ingredients) Applic. Season Harvest Reentry or Pathogens Remarks 11 Quadris 2.08FL 15.4 fl oz 92.3 fl oz 1 4 hrs Anthracnose Limit is 4 appl/crop & (Azoxystrobin) Belly rot alternate chemistry. Labeled for all cucurbits. Downy mildew See lable for tankmixing various leaf spots restrictions. Powdery mildew11 & M5 Quadris Opti 3.2 pt See label 1 0.5 Anthracnose Limit is 4 appl/crop for (Azoxystrobin & Belly rot all QoI fungicides. Do Chlorothalonil) not make more than two consecutive applications. Downy mildew Labeled for all cucurbits. various leaf spots Do not apply to mature watermelons under dry, Powdery mildew hot and other environ- mental conditions listed on label.11 Reason 500SC 5.5 fl oz 22 oz 14 0.5 Downy mildew Limit is 4 appl/crop & (Fenamidone) Alternaria leaf spot alternate chemistry. Labeled for all cucurbits.11 Sovran 4.8 oz 19.2 oz 0 0.5 Powdery mildew Follow resistance man- (Kresoxim-methyl) Gummy stem blight agement guidelines on label. Labeled for all cucurbits.13 Quintec 6 fl oz See label 3 0.5 Powdery mildew Do no make more than (Quinoxyfen) 4 appl. Do not make more than two consecu- tive appls . Not labeled on all cucurbits; labeled on various melons, can- taloupe, winter squash, gourds, pumpkins, and watermelon.19 PH-D 6.2 oz 31 oz 0 4 hrs Powdery mildew Use in alteration with (Polyoxin D zinc salt) Gummy stem blight fungicides that have dif- ferent modes of action. Gray mold Labeled for all cucurbits. various leaf spots21 Ranman 2.75 fl oz 16.5 fl oz 0 0.5 Downy mildew Limit is 6 appl/crop. (Cyazofamid) Phytophthora blight Follow resistance man- agement guidelines on label. Labeled for all cucurbits. 22 & M3 Gavel 75DF 2 lb 16 lb 5 2 Alternaria leaf spot Limit is 8 appl/crop. (zoxamide & mancozeb) Cercosopora leaf spot Some cantaloupe variet- ies are sensitive, check Downy mildew label. Labeled for all cucurbits.27 Curzate 60DF 3.2 oz See 3 0.5 Downy Mildew Use only with a labeled (Cymoxanil) Remarks rate of protectant fun- gicide. No more than 9 appl/12 months. Labeled for all cucurbits.
Page 102 Vegetable Production HandbookTable 7. Continued. Max Rate/Acre Minimum Days toFungicide Chemical Pertinent DiseasesGroup (active ingredients) Applic. Season Harvest Reentry or Pathogens Remarks 27 & 11 Tanos 50DF 8 oz See label 3 0.5 Downy mildew Limit is 4 appl/crop. (Cymoxanil & and remarks Anthracnose Must tankmix with a con- Famoxadone) tact fungicide. Limit is 72 oz/A maximum/year. Bacteria fruit blotch Labeled for all cucurbits. Phytophthora blight foli- ar and fruit phase only (disease suppression)28 Previcur Flex 1.2 pt 6 pt 2 0.5 Downy Mildew Use a tank mix partner. Promess Pythium See label for directions using a contact fungicide (Propamocarb hydrochlo- and Pythium suppres- ride) sion. Labeled for all cucurbits.33 Aliette 80WDG 5 lb 35 lb 12 hr 0.5 Downy mildew Limit is 7 appl/crop. Do Legion 80WDG Phytophthora root and not tank mix with copper fruit rot fungicides. Labeled for all cucurbits. See label Linebacter WDG for specific brand. (Fosetyl-Al)33 (Potassium phosphite) SEE INDIVIDUAL 0 4 hrs Downy mildew Check label for required Many brands available: LABELS minimum gall/acre, restrictions for use fol- Alude, Fosphite, Pythium spp. lowing copper appl., Fungi-phite, Prophyte Phytophthora spp. plant and environmental Phorcephite, Phostrol, conditions that restrict Rampart, Reveille, Topaz use, and for compatibility with other materials. Not all diseases labeled for each brand; see label.40 Acrobat 50WP 6.4 oz 32 oz 0 0.5 Downy mildew Limit is 5 appl/crop. (Dimethomorph) Phytophthora blight Tank mix with another fungicide. Harvest after spray is dry. Labeled for all cucurbits.40 Forum 6 oz 30 oz When spray 0.5 Downy Mildew Limit is 5 appl/ crop. (Dimethomorph) is dried Phytophthora blight and Apply with another fun- crown rot gicide that has a differ- ent mode of action and alternate . Minimum gal- lons per acre required. Labeled for all cucurbits.40 Revus 8 fl oz 32 fl oz 0 4 hrs Downy mil- An adjuvant is recom- (Mandipropamid) dew Phytophthora mended for best control. blight(supression) Limit is 4 appl./crop43 Presidio 4 fl oz 12 fl oz 2 0.5 Downy mildew Tankmix with another (Fluopicolide) Phytophthora blight fungicide product with a different mode of action. Labeled for all cucurbits.44 Cease SEE INIDIVIDUAL 0 4 hrs Bacterial fruit blotch Labeled for all cucurbits. Rhapsody Cease LABELS Downy mildew Tank mix with another registered fungicide Serenade ASO Gummy stem blight Serenade Max Powdery mildew Rhapsody Cease Gummy stem blight (Bacillus subtilis strain Certain leaf spots QST 713)
Chapter 9: Cucurbit Production in Florida Page 103Table 7. Continued. Max Rate/Acre Minimum Days toFungicide Chemical Pertinent DiseasesGroup (active ingredients) Applic. Season Harvest Reentry or Pathogens RemarksP Actigard 50WG 1 oz/A 8 oz 0 0.5 Downy mildew Apply preventively prior (Acibenzolar-S-methyl) Powdery Mildew disease development. Suppression of disease. Scab Labeled for all cucurbits. Bacterial fruit blotch Angular leaf spotP Regalia 1.0% 0 4 hrs Powdery mildew For use in Organic pro- (Extract of Reynoutria vol:vol Downy Mildew duction. Use 1 qt Regalia sachalinensis) dilution Phytophthora blight plus labeled copper fun- gicide for Phytophthora Gummy stem blight blight.NC Actinovate AG See label for use as soil 0 0 See label for disease Use an intregrated pest (Streptomyces lydicus drench or foliar spray suppression management strategy. WYEC 108) Product is OMRI listed.NC JMS Stylet Oil 3 qt - 4 hrs Aphid-transmitted virus- See label for specific (praffinic oil) es, powdery mildew appl. Tech. (e.g. use of 400 psi)NC Oxidate Various dilution rates; 0 1 hr Downy mildew See label for specific (hydrogen dioxide) SEE LABEL Powdery mildew instructions for use with cucurbits. Gummy stem blight AnthracnoseNC Sonata 4 lb 0 4 hrs Powdery mildew Tank mix with another (Bacillus pumilus strain Downy mildew registered fungicide QST 2808)
Page 104 Vegetable Production HandbookTable 8. Selected insecticides approved for use on insects attacking cucurbit crops. Trade Name Rate REI Days to MOA (Common Name) (product/acre) (hours) Harvest Insects Code1 Notes Acramite-50WS 0.75-1.0 lb 12 3 twospotted spider mite un One application per season. (bifenazate) Actara 1.5-5.5 oz 12 0 aphids, flea beetles, whiteflies, sup- 4A Apply before pests reach damaging (thiamethoxam) pression of cucumber beetles and levels. leafminers at higher rates Admire Pro 7-10.5 oz 12 21 (soil) aphids, cucumber beetles, leaf- 4A Will not control thrips in flowers. (imidacloprid) hoppers, foliage-feeding thrips, Do not use with other Group 4A whiteflies insecticides (see appropriate labels for other brands) Admire Pro 0.44 fl oz/10,000 12 21 aphids, whiteflies 4A Planthouse: One application to (imidacloprid) plants transplants. See label for use on mature greenhouse cucumbers. Agree WG 0.5-2.0 lb 4 0 lepidopteran larvae (caterpillar 11 Apply when larvae are small for (Bacillus thuringi- pests) best control. OMRI-listed2. ensis subspecies aizawai) *Agri-Mek SC 1.75-3.50 fl oz 12 7 leafminers, spider mites 6 Minimum of 7 days between appli- (abamectin) cations. No more than 2 sequential applications. Must be mixed with an adjuvant-see label for types. *Ambush 25W 6.4-12.8 oz 12 0 cabbage looper, cucumber beetle 3 Do not apply more than 1.6 lb ai/ (permethrin) adults, cutworms, leafminers, Lygus acre per season. bug, melonworm, pickleworm, plant bugs, rindworms, squash bugs, squash vine borer, stink bugs *Asana XL (0.66 EC) 5.8-9.6 fl oz 12 3 cabbage looper, corn earworm, 3 Do not apply more than 0.25 lb ai/ (esfenvalerate) cucumber beetles (adults), cut- acre per season, (or 5 applications worms (seedling spray), grasshop- at high rate). pers, leafhoppers, Lygus bug, pick- leworm, rindworms, squash bug, squash vine borer, stink bugs Assail 30SG 2.5-5.3 oz 12 0 aphids, cucumber beetles, leafhop- 4A No more than 5 applications per (acetamiprid) pers, melonworm, pickleworm, season. Do not use if another squash bug, squash vine borer, group 4A insecticide has been whiteflies used. Avaunt 2.5-6.0 oz 12 3 beet armyworm, cabbage looper, 22 Do not apply more than 24 oz/acre (indoxacarb) melonworm, pickleworm per crop. Aza-Direct 1-2 pts, up to 3.5 4 0 aphids, beetles, caterpillars, leaf- un Antifeedant, repellant, insect (azadirachtin) pts, if needed hoppers, leafminers, mites, stink growth regulator. OMRI-listed2. bugs, thrips, weevils, whiteflies Azatin XL 5-21 fl oz 4 0 aphids, beetles, caterpillars, leaf- un Antifeedant, repellant, insect (azadirachtin) hoppers, leafminers, thrips, weevils, growth regulator. whiteflies *Baythroid XL 0.8-2.8 fl oz 12 0 armyworms (1st and 2nd instars), 3 Maximum amount per season: (beta-cyfluthrin) cabbage looper, corn earworm, 11.2 fl oz/acre. cucumber beetles, cutworms, grasshoppers, melonworm, pick- leworm, rindworms, stink bugs, tobacco budworm Belay 50 WDG 1.6-3.2 oz 12 7 aphids, cucumber beetles, flea 4A Do not apply more than 6.4 oz (clothianidin) beetles, leafhoppers, leafminers per acre per season. Do not use (suppression), squash bug, stink an adjuvant. Do not apply during bugs, whiteflies (suppression) bloom. Rates higher than 2.1 oz are for Florida only (supplemental label).
Chapter 9: Cucurbit Production in Florida Page 105Table 8. Continued. Trade Name Rate REI Days to MOA (Common Name) (product/acre) (hours) Harvest Insects Code1 Notes Belay 50 WDG 4.8 -6.4 oz 12 Apply at aphids, cucumber beetles, flea bee- 4A Do not apply more than 6.4 oz (clothianidin) (soil application) planting tles, leafhoppers, leafminers (sup- per acre per season. See label for pression), whiteflies (suppression) application instructions. Beleaf 50 SG 2.0-2.8 oz 12 0 aphids, plant bugs 9C Do not apply more than 8.4 oz/ (flonicamid) acre per season. Begin applica- tions before pests reach damaging levels. Biobit HP 0.5-2.0 lb 4 0 caterpillars (will not control large 11 Treat when larvae are young. Good (Bacillus thuringi- armyworms) coverage is essential. Can be used ensis subspecies in the greenhouse. OMRI-listed2. kurstaki) BotaniGard 22 WP, WP: 4 0 aphids, thrips, whiteflies -- May be used in greenhouses. ES 0.5-2 lb/100 gal Contact dealer for recommenda- (Beauveria bassiana) ES: tions if an adjuvant must be used. Not compatible in tank mix with 0.5-2 qt/100 gal fungicides. *Brigade 2 EC 2.6-6.4 fl oz 12 3 aphids, armyworms, cabbage 3 Do not apply more than 19.2 (bifenthrin) looper, corn earworm, cucumber ounces of product per acre per beetles, cutworms, grasshoppers, season. Do not make more than 2 leafhoppers, melonworm, mites, applications after bloom. pickleworm, plant bugs, rindworms, squash bug, squash vine borer, stink bugs, tobacco budworm Coragen 2.0-7.5 fl oz – 4 1 beet armyworm, cabbage looper, 28 May be applied through drip (rynaxypyr) drip, 3.5-7.5 – soil leafminer larvae, melonworm, pick- (chemigation),as well as to soil at at planting, 2.0-7.0 leworm, suppression of whitefly planting or as a foliar spray. – foliar nymphs Courier 40SC 9.0-13.6 fl oz 12 7 leafhoppers, planthoppers, white- 16 Insect growth regulator. Do not (buprofezin) flies make more than 2 applications per season per crop or 4 per year. See label for crop rotational restric- tions. Crymax WDG 0.5-2.0 lb 4 0 caterpillars 11 Use high rate for armyworms. (Bacillus thuringi- Treat when larvae are young. ensis subspecies kurstaki) *Danitol 2.4 EC 10.67-16 fl oz 24 7 banded cucumber beetle, cabbage 3 Do not exceed 42.67 fl oz per acre (fenpropathrin) looper, fall armyworm, southern per season. green stink bug, plant bug, striped cucumber beetle, spider mite, yel- lowstriped armyworm Deliver 0.25-1.5 lb 4 0 caterpillars 11 Use higher rates for armyworms. (Bacillus thuringi- OMRI-listed2. ensis subspecies kurstaki) *Diazinon 50 W, AG500: 2-4 qt 72 preplant cutworms, wireworms 1B Melons and watermelons only. *AG500 50W: 4-8 lb Not for squash or cucumbers. One (diazinon) application per year. *Dibrom 8E 1 pt 48 1 aphids, armyworms, cucumber 1B Summer squash and netted vari- (naled) beetles, loopers, thrips eties of cantaloupe only. Do not use if temperature is >90°F. Dimethoate 4 EC melons: 1 pt 48 3 aphids, leafhoppers, leafminers, 1B Highly toxic to bees. Not for (dimethoate) watermelons: 0.5 thrips squash or cucumber. – 1 pt
Page 106 Vegetable Production HandbookTable 8. Continued.Trade Name Rate REI Days to MOA(Common Name) (product/acre) (hours) Harvest Insects Code1 NotesDiPel DF 0.5-2.0 lb 4 0 caterpillars 11 Treat when larvae are young. Good(Bacillus thuringi- coverage is essential. For organicensis subspecies production.kurstaki)Durivo 10-13 fl oz 12 30 aphids, flea beetles, leafhoppers, 4A, 28 May be applied via one of several(thiamethoxam, melonworm, pickleworm, thrips, soil application methods—se labelchlorantraniliprole) whiteflies, suppression of leafmin- for details. ers and cucumber beetlesEntrust 1.25-2.5 oz 4 3 armyworms, cabbage looper, 5 Do not apply more than 9 oz per(spinosad) leafminers, loopers, melonworm, acre per crop. OMRI-listed2. pickleworm, rindworms, thripsEsteem Ant Bait 1.5-2.0 lb 12 1 red imported fire ant 7C Apply when ants are actively forag-(pyriproxyfen) ing.Extinguish 1.0-1.5 lb 4 0 fire ants 7A Slow‑acting IGR (insect growth((S)‑methoprene) regulator). Best applied early spring and fall where crop will be grown. Colonies will be reduced after three weeks and eliminated after 8 to 10 weeks. May be applied by ground equipment or aerially.Fulfill 2.75 oz 12 0 green peach aphid, melon aphid, 9B Minimum of 7 days between appli-(pymetrozine) suppression of whiteflies cations. Maximum 5.5 oz/acre/ season.Intrepid 2F 4-10 oz 4 3 beet armyworm, cabbage looper, 18 Do not make more than 4 applica-(methoxyfenozide) melonworm, pickleworm, rind- tions per season. worms, southern armyworm, true armyworm, yellowstriped army- wormJavelin WG 0.12-1.50 lb 4 0 most caterpillars, but not 11 Treat when larvae are young.(Bacillus thuringi- Spodoptera species (armyworms) Thorough coverage is essential.ensis subspecies OMRI-listed2.kurstaki)Knack IGR 8-10 fl oz 12 7 whiteflies (immatures) 7C Do not apply more than twice per(pyriproxyfen) season. Do not apply less than 8 oz per acre per application.Kryocide 8-16 lb 12 14 cabbage looper, Diabrotica beetles un Do not exceed 64 lb/acre per sea-(cryolite) (8-12 for cucum- 7 - sum- (cucumber beetles), flea beetles, son, 48 for cucumber. ber) mer melonworm, pickleworm squash only*Lannate LV LV: 1.5-3.0 pt 48 1=1.5 pts beet armyworm, cucumber beetles, 1A Not for use on winter squashes(methomyl) 3=1.5+ fall armyworm, flea beetles, such as butternut or acorn - only pts granulate cutworms, loopers, melon for summer squash, cucumbers, aphid, melonworm, pickleworm, and melons. tobacco budworm, variegated cut- worm, yellowstriped armyworm*Lannate SP SP: 0.5-1.0 lb 48 1=1/2 lb See above 1A See above(methomyl) 3=1/2+ lbMalathion 8 1.75 pt 12 1 aphids, cucumber beetles, leafmin- 1B Squash and cucumbers only.(malathion) ers, mites, pickleworm, squash vine borerM-Pede 49% EC 1-2%V/V 12 0 aphids, leafhoppers, mites, plant – OMRI-listed2.(Soap, Insecticidal) bugs, thrips, whiteflies*MSR Spray 1.5-2.0 pt 14 days 14 aphids, cucumber beetles, mites 1B Do not apply more than 1 time perConcentrate (oxy- season.demeton‑methyl)
Chapter 9: Cucurbit Production in Florida Page 107Table 8. Continued. Trade Name Rate REI Days to MOA (Common Name) (product/acre) (hours) Harvest Insects Code1 Notes Neemix 4.5 4-16 fl oz 12 0 fall armyworm, leafminers, mel- un IGR and feeding repellant. (azadirachtin) onworm, pickleworm, rindworms, Greenhouse and field use. OMRI- squash bug, squash vine borer, listed2. tobacco budworm, whitefly Oberon 2SC 7.0-8.5 fl oz 12 7 twospotted spider mite, whiteflies 23 Maximum amount per crop: 25.5 (spiromesifen) fl oz/acre. No more than 3 appli- cations. See label for plant-back intervals. Oil, Insecticidal 1-2 gal/100 gal 4 0 aphids, leafhoppers, leafminers, -- Organic Stylet-Oil and Saf-T-Side SunSpray 98.8% mites, thrips, whiteflies, aphid- are OMRI- listed2. transmitted viruses (JMS) Ultra-Fine 3-6 qt/100 gal JMS Stylet Oil, Saf- (JMS) T-Side, Others Platinum 5-11 fl oz 12 30 aphids, flea beetles, leafhoppers, 4A For most crops that are not on the (thiamethoxam) thrips, whiteflies, suppression of label, a 120-day plant-back interval cucumber beetles and leafminers must be observed. Platinum 75SG 1.66-3.67 oz Portal 2.0 pt 12 3 Mites (including broad mite), white- 21A Melons and watermelons only. (fenpyroximate) flies Two applications per season. *Pounce 25 WP 6.4-12.8 oz 12 0 aphids, cabbage looper, cucumber 3 Use high rate for aphids and (permethrin) beetles, cutworms, leafhoppers, squash bug. Do not apply more leafminers, melonworm, pickle- than 1.2 lb ai/acre per season (0.8 worm, plant bugs, rindworms, lb ai for cantaloupes). squash bug, squash vine borer Prokil Cryolite 96 8-16 lb 12 14 cabbage looper, Diabrotica beetles un Do not apply more than 80 lb/acre (cryolite) (cucumber beetles), flea beetles, per season. Not for cucumbers. melonworm, pickleworm 7 for summer squash Pyganic 5.0 4.5-18 oz 12 0 many insects 3 Treat when insects first appear. (pyrethrins) Harmful to bees. OMRI-listed.2 Pyronyl Crop Spray 1-12 fl oz 12 12 hours ants, aphids, armyworms, cabbage 3 Can be used on greenhouse veg- (pyrethrin + pipero- looper, corn earworm, cucumber etables. nyl butoxide) beetles, flea beetles, leafhoppers, thrips, whiteflies Radiant SC 5-10 fl oz 4 3 armyworms (not yellowstriped), 5 No more than 6 applications or 34 (spinetoram) 1 for cabbage looper, leafminers, mel- fl oz per acre per crop. cucum- onworm, pickleworm, rindworms, bers thrips Requiem 2 -3 qt 4 0 green peach aphid, thrips, whiteflies un Apply before pests reach damaging (extract of levels. Chenopodium ambrosioides) Rimon 0.83EC 9-12 fl oz 12 1 armyworms, cucumber beetles, 15 Do not apply more than 36 oz per (novaluron) leafminers, loopers, melonworm, acre per season or apply more pickleworm, sap beetles, squash often than every 14 days. Do not bugs, thrips, whiteflies use adjuvants. Sevin 80S, 4F, XLR 80S: 0.63-1.25 lb 12 3 cucumber beetles, flea beetles, leaf- 1A Do not apply more than 7.5 lb (carbaryl) 4F, XLR: 0.5-1.0 qt hoppers, melonworm, pickleworm, (80S) or 6 qt (4F, XLR) per acre squash bug per year. Do not apply when plants are wet. Sulfur See label 24 1 mites --
Page 108 Vegetable Production HandbookTable 8. Continued.Trade Name Rate REI Days to MOA(Common Name) (product/acre) (hours) Harvest Insects Code1 NotesSynapse WG 2.0-3.0 oz 12 1 armyworms, cabbage looper, corn 28 Do not apply more than 9 oz per(flubendiamide) earworm, cutworms, melonworm, acre per season. pickleworm, rindworms, squash vine borer*Telone C‑35 See label 5 days preplant symphylans, wireworms -- See supplemental label for use(dichloropropene + restrictions in south and centralchloropicrin) Florida.*Telone II(dichloropropene)*Thionex 50W 1-2 lb 96 h, Melons aphids, cabbage looper, cucumber 2 Do not make more than 4 applica-(endosulfan) except and beetles, melonworm, pickleworm, tions per year or exceed 2.0 lb pump- summer rindworms, squash beetle, squash active ingredient per acre per year. kins and squash: bug, squash vine borer, striped flea This product cannot be used after winter 4, cucum- beetle, whitefly July 31, 2012, except on pump- squash bers, kins and winter squash until Dec. (12 days) pumpkins, 31, 2014. winter squash: 16Trigard 2.66 oz 12 0 leafminers 17 Do not make more than six appli-(cyromazine) cations.Trilogy 0.5-2.0% V/V 4 0 aphids, mites, suppression of thrips un Apply morning or evening to(extract of neem oil) and whiteflies reduce potential for leaf burn. Toxic to bees exposed to direct treat- ment. OMRI-listed2.Venom Insecticide foliar: 1-4 oz 12 foliar: 1 Foliar: brown stink bug, cucumber 4A Do not apply more than 6 oz per(dinotefuran) soil: 5-7.5 oz soil: 21 beetles, flea beetles, grasshoppers, acre per season (foliar) or 12 oz suppression of green peach aphid (soil) per acre per season. Use and melon aphid, green and south- only one application method (soil ern green stink bugs, squash bug or foliar). Note that pests con- Soil: leafhoppers, leafminers, trolled differ depending on applica- southern green stink bug, squash tion method. Supplemental label bug thrips, whiteflies, suppression needed. of green peach aphid and melon aphidVetica 12.0-17.0 fl oz 12 7 armyworms, cabbage looper, corn 28, 16 Do not apply more than 3 times(flubendiamide and earworm, cutworms, melonworm, per crop season or apply morebuprofezin) suppression of leafhoppers, pickle- than 38 fl oz per acre per sea- worm, squash vine borer, tobacco son. Same active ingredients as budworm, leafhoppers, whiteflies Synapse, Coragen, and Courier. Use higher rates for leafhoppers and whiteflies.Voliam Flexi 4-7 oz 12 1 aphids, cabbage looper, corn ear- 4A, 28 Highly toxic to bees exposed to(thiamethoxam and worm, flea beetles, melonworm, direct treatment or residues onchlorantraniliprole) pickleworm, rindworms, tobacco blooming crops. budworm, whiteflies, suppression