This document discusses various strategies for optimizing water use in container plant production. It addresses factors like how much water to apply based on leaching fraction, applying water in cycles to improve distribution, grouping plants by water needs, and timing irrigation for different growth stages and times of day. Proper substrate selection and amendments can also increase water efficiency and maximize growth.

1. Wise Water Use for Container Production Jim Owen, Jr. North Willamette Research and Extension Center

5. 0.5 to 1.0 inch

7. Leaching Fraction Lined or sealed Sealed outside pot Leaching Fraction = Volume Leached / Volume Applied Bilderback, personal communication

8. Total Water Applied for container diameter area is measured as “total volume” to calculate leaching fraction Bilderback, personal communication

9. Leaching Fraction ~ 0.20 Bilderback, personal communication

10. Plastic bags work for leaching fractions too! Water Applied Water Leached

11. Leaching fraction Owen. 2006

12. Leaching fraction 7 gal per container Owen. 2006

13. Leaching fraction 7 gal per container 90,000 gallons of water saved per growing acre while maintaining growth Owen. 2006

16. Cyclic Irrigation Lateral unsaturated flow Wetting front 0.2 leaching fraction 1st irrigation cycle (some channeling) 2nd irrigation cycle 3rd irrigation cycle Ted Bilderback (personal communication)

17. Cyclic irrigation Fain, Tilt, Sibley. 2000. Less is More! Highlights of Agriculture Research red maple red maple

18. Cyclic irrigation Fain, Tilt, Sibley. 2000. Less is More! Highlights of Agriculture Research red maple 25% increase in dry weight 150% increase (0.5 in) in red maple caliper

22. Plant Growth Stage Transplant / shift

23. Plant Growth Stage Growing / production

24. Plant Growth Stage Sale / Holding / Retail

26. Substrate Texture 0 2 4 6 Height (inches) medium fine Owen and Altland. 2006.

27. Substrate Texture 32% (70 mL) 49% (108 mL) 37% (77 mL) 0 2 4 6 Height (inches) medium fine Owen and Altland. 2006.

28. Substrate Texture 32% (70 mL) 49% (108 mL) 37% (77 mL) 0 2 4 6 Height (inches) 36% (76 mL) 62% (138 mL) 43% (89 mL) medium fine Owen and Altland. 2006.

29. Substrate Amendment

30. Substrate Amendment Owen. 2006

31. Substrate Amendment 8 gal per container Owen. 2006

32. Substrate Amendment 107,000 gallons of water saved per growing acre while maximizing growth Owen. 2006

35. Irrigation timing c b a b

36. Irrigation timing – micro-irrigation Warren and Bilderback. 2002. J. Environ. Hort c b a b

37. Irrigation timing – micro-irrigation Warren and Bilderback. 2002. J. Environ. Hort

38. Irrigation timing – micro-irrigation Warren and Bilderback. 2002. J. Environ. Hort

39. Irrigation timing – micro-irrigation Warren and Bilderback. 2002. J. Environ. Hort 3:00 PM 11:00 PM

40. Irrigation timing c b a b

41. Irrigation timing - overhead Williamson et al. 2005. SNA Cotoneaster dry weight (g) Pre-Dawn All Day PM a a b

42. Irrigation timing - overhead Williamson et al. 2005. SNA 20 25 30 35 40 45 50 1 7 13 19 1 7 13 19 1 7 13 19 pre-dawn all day pm Substrate temperature (C) Aug 26 Aug 27 Aug 28

43. Irrigation timing - overhead Williamson et al. 2005. SNA Substrate Temperature (C) Aug 26 Aug 27

44. Irrigation timing - overhead Williamson et al. 2005. SNA Substrate Temperature (C) Aug 26 Aug 27 12:00 3:00 6:00 Pre-Dawn

45. Irrigation timing - overhead Williamson et al. 2005. SNA Substrate Temperature (C) Aug 26 Aug 27 3:00 AM 9:00 PM

50. Plant Architecture Williamson et al. 2005. SNA

51. Plant Architecture 0 100 200 300 400 500 600 700 800 900 22 29 32 40 47 49 54 66 73 82 92 99 105 Days After Initiation Daily Volume applied (ml) Cotoneaster Vitex Williamson et al. 2005. SNA Cotoneaster dammeri ‘Skogholm Vitex trifolia ‘Variegata’

52. Plant Architecture 0 100 200 300 400 500 600 700 800 900 22 29 32 40 47 49 54 66 73 82 92 99 105 Days After Initiation Daily Volume applied (ml) Cotoneaster Vitex Williamson et al. 2005. SNA Cotoneaster dammeri ‘Skogholm Vitex trifolia ‘Variegata’

53. Plant Architecture Williamson et al. 2005. SNA 60 80 100 120 140 160 180 200 220 240 260 33 50 72 92 105 Days Percentage irrigation Capture Cotoneaster Gardenia Gardenia augusta ‘Chuck Hayes’ Cotoneaster dammeri ‘Skogholm

54. Plant Architecture Williamson et al. 2005. SNA 60 80 100 120 140 160 180 200 220 240 260 33 50 72 92 105 Days Percentage irrigation Capture Cotoneaster Gardenia Gardenia augusta ‘Chuck Hayes’ Cotoneaster dammeri ‘Skogholm

55. Plant Architecture Williamson et al. 2005. SNA Daily Volume Applied (L) Percentage Capture (%)

56. Plastic bag method FIELD QUANTIFICATION OF SUBSTRATE PHYSICAL PROPERTIES Cook, A., T. Bilderback, and M. Lorscheider. 2004. Physical Property Measurements in Container Substrates: A Field Quantification Strategy. Southern Nursery Association Research Proceedings 49:102-104

58. Field Quantification Known container volume Cook et al. 2004. SNA

59. Field Quantification Fill, pack, remove excess Cook et al. 2004. SNA

60. Field Quantification Saturate with known volume = total porosity (weight can also be used) Cook et al. 2004. SNA

61. Field Quantification Drain a known volume = air space Cook et al. 2004. SNA

62. Field Quantification Container Capacity = total porosity - air space Cook et al. 2004. SNA

63. Field Quantification Bulk Density = dry weight / container volume Cook et al. 2004. SNA

65. North Willamette Research and Extension Center http://oregonstate.edu/dept/NWREC/