Soil performs certain roles that support plants during their growth and development. A good soil provides anchorage and stability to plant roots. Its structure has enough pores to allow air to circulate and provide oxygen for root respiration and other processes. It has good water-holding capacity so that plant roots can absorb the water needed for plant growth. However, it should not hold so much water that it forces out the air that plant roots need to respire. In other words, there should be a balance between its water-holding capacity and drainage properties. Lastly, a good soil will be a source of nutrients for plant roots to absorb – whether provided through breakdown of organic matter in the soil or simply the ability to hold on to the nutrients provided when the gardener applies fertilizer.
The analysis of a fertilizer states the quantity and type of nutrients contained in the container. This is indicated by 3 numbers on the container that always stand for the same thing, in the same order. The first number is the percentage of nitrogen contained in the fertilizer – in this case, 32%; the second number refers to percentage of phosphorus in the form of phosphorus pentoxide (P2O5) – in this case, 10%, and the third number is the percentage of potassium in the form of potash (K2O) – in this case 10%. Balanced fertilizers contain these three elements in equal percentages – for example 10-10-10. A complete fertilizer contains all 3 elements but not necessarily equal percentages. A single-element fertilizer contains only one element. Many things must be considered when choosing the proper fertilizer – most important is the nutrient balance and the form of the fertilizer. These factors should be considered when trying to compare prices for the best deal.
ymptoms:Phosphorus deficiency is most often manifested as purpling of the leaves, particularly the leaf veins. In severe cases the whole plant may take on a purple hue. Tomato roots growing in cold soil, either in the greenhouse or the field, take up phosphorus poorly. Deficient plants lose vigor and yield poorly.Control:While phosphorus deficiency due to improper fertility may be a problem in hydroponic, pot culture, and some sandy soil conditions, it is most likely a result of cool root zone temperatures. Plastic mulch will alleviate the problem in early field plantings, and a balanced liquid feed fertilizer will alleviate the problem in greenhouse and pot culture.
Potassium also has many essential functions in plants, including sugar formation and movement in plants, formation of chlorophyll, and leaf stomate opening and closing for gas exchange with the air. Like nitrogen, potassium is very prone to leaching in soils. And plants will tend to take up as much as you want to give them – even if they don’t need it, so it’s easy to waste money on excess fertilizer. Also, over-fertilizing with potassium (and nitrogen for that matter) will injure plants by killing the root and leaf tips.
Grow Your Own, Nevada! Fall 2011: Basic Soils, Watering and Fertilizing
Basic Soils, Watering and Fertilizing Heidi Kratsch University of Nevada Cooperative Extension
Soil and Plants Anchorage and stability Aeration Water Nutrients
Depth (Feet) 0 SAND SILT 1 CLAY 2 3Water movement through different soil types
What affects water loss fromplants? Sunlight Temperature Humidity Wind
Large leaves have more pores What our eyes see What our eyes can‟t see
How to water your plants Applying too much water at one time leaches nutrients from the soil. Applying water too frequently suffocates roots.
Get your hands in the soil! Dig down 4 to 6 inches in the soil. If the soil feels dry and crumbly, it‟s time to water.
Deep watering encourages deeprootsDeep rooted plants are less susceptible to water stress
How much do I water? Sandy soils need water more frequently. Water more frequently in hot weather. New seedlings or transplants need more frequent watering. Large, deep-rooted plants need deeper watering.
Watering methods Hand watering Time consuming Are you providing consistent amounts to each plant?
Watering methods Furrow irrigation Wide and shallow rows (no more than 3-4 inches deep) Must have level ground. Best with large plants (like tomato) in sandy soils.
Watering methods Soaker hose Easy Inexpensive Saves water Hoses must be replaced often.
Water methods… Drip irrigationMulch topreventwaterevaporation
Stake tubing to keep in place Internal emitter
External emitter staked on a riserAttach an externalemitter to the endof ¼-inch feederline and stake witha riser to mistplants.
Ends must be capped or clamped tomaintain water pressure. Hose end cap Hose end clamp
Need a water source Automatic timer Main line Filter riser Pressure regulat
Purchasing Fertilizers Terminology: Balanced (16-16-16) Complete (5-10-15) Single element (46-0-0) Numbers refer to percentages of nitrogen (N), phosphorus (P), and potassium (K) N P K
Organic vs. synthetic fertilizersSynthetic Organic Provide a quickly Goal is to enhance released source of soil for beneficial nutrients on demand microbes that can Can cause leaching decompose organic Fertilizer burn matter. Slowly released Timing is important! Lower nutrient values Look for certified organic products.
Organic fertilizersOrganic sources of N Synthetic sources of N Bat guano Ammonium sulfate Blood meal Ammonium nitrate Cottonseed meal Urea Fish emulsion Fish mealOrganic source of P Bone meal
Nitrogen Deficiency Reduced growth Smaller leaves Chlorosis (yellowing) Common in sandy soils low in organic matter Over-irrigation
Phosphorus Deficiency Important in flower, fruit, and root development More often a result of cold soils – roots cannot take up the nutrient Common ingredient in Purpling of leaf veins from phosphorus “starter” fertilizers deficiency
Potassium Deficiency Many functions including movement of sugars in plants Leaches readily from soils – do not overwater. Potassium deficiency of soybean plants
Nevada soils are alkaline Alkaline soils: pH is above 7 Soils that have not been greatly weathered or leached Soils high in calcium Reduces solubility of all micronutrientsAdapted from library.thinkquest.org by A. Miller
Fertilizing is a two-step process FIRST: Leafy Root Use a balanced Use a low N complete fertilizer early in the fertilizer early in the season. season: 10-10-10 6-24-24 16-16-16 6-12-18 8-16-16eavy feeders require a SECOND fertilization with N during the seaso Corn, garlic, onions, potatoes
Sidedressing Apply fertilizer 3 to 6 inches to one side of plant or row. Water it in. Keep dry fertilizer off the leaves.
Artichokes Grow from transplants or seed (transplant 3- „Green Globe‟ heirloom 4 weeks before FF date). Requires cool temps to initiate a flower stalk. Drip irrigation is best; keep soil moist; roots are shallow. Artichokes are flower buds. Requires high N (21- 0-0) every 4 weeks starting 1 month after transplant.
Beans Water: „Blue Lake‟ – pole type Keep soils moist but not wet. Water most critical during flower and pod development. Fertilize: Work 8-16-16 fertilizer into soil before planting. No fertilizer after that.Lack of flower development or “stringy” beans indicate water or heHarvest before bean seeds develop – beans become tough.
Peas Watering: Regular watering, „Super Sugar Snap‟ especially at time of flowering. Harvest when pods are plump. Fertilizing: Incorporate 8-16-16 pre-plant. No further N required; Stringy peas are caused by plants fix their own N. heat or water stress.
Beets Grow from seed. Water regularly using „Detroit Dark Red‟ drip irrigation to keep soil moist. Moisture fluctuations cause root cracking. Fertilize before planting with 8-16-16. Weed control is Heat and water stress may essential! cause woody beets.
Carrots “Double-dig” heavy soils. „Imperator‟ Water Use drip irrigation if possible. Avoid over-watering to prevent hairy roots and forking. Fertilize: Apply 8-16-16 pre- Uneven watering causes root cra plant. No further N required.
Broccoli Best grown as transplants. „Calabrese‟ heirloom Water: Deeply and infrequently to encourage deep roots. Use mulch to conserve water and control weeds. Fertilize: Pre-plant fertilize with “Buttoning” soon after transplant balanced fertilizer (16- can be caused by water or 16-16). nutrient stress. Sidedress with (21-0-0) 4 weeks after planting.
Brussels sprouts Grow from seed started indoors. „Long Island Improved‟ Water: Deeply and infrequently to encourage deep roots. Use drip to provide even moisture. Use mulch. Fertilize: Work balanced fertilizer into the soil before planting. Sidedress with (21-0-0) Uneven watering promotes once or twice before splitting, bitter taste and tip sprouts form. burn. Avoid fertilizing during Harvest sprouts from the head development. bottom up.
Cabbage Start early – plant in ground where peas „Red Acre‟ grew last year. Water: Water deeply and frequently. Moisture fluctuations may cause head “splitting.” Keep heads up out of the soil. Fertilize: Work balanced fertilizer Tip burn also occurs in cabbage. into the soil before Uniform irrigation with moderate planting. fertilization will prevent this Sidedress with (21-0-0) problem. 4 weeks after
Cabbage/brussels sprout tip burn Calcium not transported to rapidly expanding tissues. Common in sandy soils. Caused by any condition that favors rapid growth. Avoid excess N during head formation Tip burn on brussels sprou Maintain P:K ratio of 1:1
Kale Fertilize: „Dwarf Siberian‟ Organic matter and complete all-purpose before planting Sidedress with N 4 weeks after transplanting. Water: Deeply and frequently without allowing soil Moisture fluctuations cause to dry out. kale leaves to become Use drip irrigation and tough and develop off mulch. flavors. A light frost intensifies flavor of fall- planted kale.
Lettuce Cool season veggie; temps above 80 F reduce „Black Seeded Simpson‟ seed germination. Water: Water regularly to prevent drought stress; uneven moisture causes tough leaves and off flavors. Fertilize: Work in all-purpose Lettuce tastes best when balanced pre-plant. grown rapidly and Sidedress with N after 4 harvested before the heat weeks. of summer.
Kohlrabi Least hardy of the cabbage family „Purple Vienna‟ heirloom veggies – plant seeds 1-2 weeks before last frost date. Water: Frequently – shallow roots Fertilize: Moisture fluctuations Amend soil with organic matter and cause stems to be complete fertilizer. tough and woody. Sidedress with N 3 Temperatures below weeks after planting. 45 F trigger flowering.
Leeks Water: Roots are shallow; „American Flag‟ provide water regularly. Fertilize: Amend soil with organic matter and complete all- purpose fertilizer. Sidedress with N in May and early June (fish meal works well). Mound soil around stalk (below joints) to keep stalks white and mild. Weed control is especially important during the first 2 months of growth.
„Red Bulbing onions Torpedo‟ intermediat e day Intermediate or neutral day onions best in northern „Super Star‟ white (day neutral) Nevada. Water: Water regularly due to shallow rooting. Stop watering when tops fall over. Fertilize: Work OM and all-purpose balanced fertilizer pre- If you plant your onions planting. too late in the season, Sidedress with extra N in late they may not form bulbs May and in June – affected by day
Garlic „Chesnok Red‟ hardneck Hardy perennial –plant dry bulbs late Sept to Nov. Hardneck vs softneck varieties Water regularly but stop when leaves turn brown and tops fall over. High nutrient requirements Amend soil with organic matter and complete „Early white‟ softneck fertilizer at planting.
Sweet Corn Requires maximum 90 days to maturity from seed sunlight; warm season „Silver Queen‟ white heirloom Water: Regular water, esp. during tasseling, silking and ear formation. Fertilize: Amend soils with compost + 16-8-8 fertilizer. Sidedress with 46-0-0 Drought stress during ear when plants have 8-10 formation decreases yield, leaves and again when lowers kernel quality and silks appear. affects flavor.
Cucumbers „Marketmore‟ Love sandy soils and lots of room! Fertilize before planting with all-purpose complete. Sidedress with N fertilizer when runners develop. Water deeply by drip or furrows Over- and under-watering causes: Bitter fruits Pointed ends Misshapen Cucumber plants are vining and benefit from a
New Zealand Spinach Warm season spinach variety. “New Zealand‟ Soak seeds 24 hours prior to planting. Water: will tolerate periods of drought but tastes better with even watering – Use drip irrigation. Fertilize: Incorporate organic matter prior to planting. Sidedress with OM or high- New Zealand spinach is N fertilizer through the relatively pest and season. disease free.
Potato Irregular soil moisture causes abnormal tuber Grown from “seed pieces” growth. Soils must be 50 F “Hill” soil around plants as they grow to prevent tuber “greening.” Water: Deep, regular watering with drip irrigation. Reduce water as leaves yellow and die. Fertilize: Pre-plant with balanced fertilizer Sidedress with (21-0-0) after Many potato varieties seedlings emerge. will grow in northern Nevada.
Tomatoes „Sugar Sweetie‟ cherry Grow from plants or seed. Determinate vs. indeterminate Water: Water deeply using drip Use mulch to keep soil moist. Fertilize: Amend soil with OM + balanced complete fertilizer. „Early Girl‟ bush style No fertilizer after
Blossom-end rot Occurs on blossom end of “fruits.” Caused by decreased availability to calcium Inconsistent watering practices. Apply mulch Avoid fertilization with N during early fruiting. Do NOT apply lime or gypsum.