The document discusses several principles of water-wise gardening including planning and designing landscapes for water conservation, improving soil quality, selecting drought-tolerant plants, grouping plants according to water needs, efficient irrigation methods, and good horticultural practices. It provides details on how soil type, rooting depth, evapotranspiration rates, and plant water demands influence irrigation management and recommends irrigating lawns in July every 4-5 days with 0.8-1 inch of water depending on soil conditions.

2. Irrigation Management and Water-Wise Gardening HCC100 -- Horticultural Science, The Science of Gardening

3. 7 Principles of Water-Wise Gardening

4. Planning and designing for water conservation, beauty, and utility

5. Improving the soil Add organic matter

6. Creating practical turf and non-turf areas

7. Watering efficiently with appropriate irrigation methods Irrigation efficiency has greatest water savings potential for most home gardeners.

8. Selecting plant appropriate for our climate AND Grouping them according to their water needs ( Hydrozoning ) AND Irrigating according to water need

9. Mulching to reduce evaporation

10. Maintaining with good horticultural practices Healthy plants are more tolerant of insect and disease problems. Healthy plants have fewer insect and disease problems Iron chlorosis, a symptoms of springtime over-watering

11. 7 Principles of Water-Wise Gardening Planning and design for water conservation, beauty, and utility Improving the soil Creating practical turf and non-turf areas Watering efficiently with appropriate irrigation methods Selecting plants and grouping them according to water need Mulching to reduce evaporation Maintaining with good horticultural practices

12. Planning and designing for water conservation, beauty, and utility

13. Create a base plan Make a simple drawing of the property Typical scale is 8-10 feet per inch Show site amenities Buildings Hardscape features (driveways, walks, patio, deck) Existing plant materials Utility lines Site limitations Sun exposure Wind patterns Drainage issues

16. Landscaping on Expansive Soils CSU Cooperative Extension Fact Sheet #7.236

17. Make a bubble diagram Use areas (identifying irrigation needs ) Lawns Routine, reduce, low and non-irrigated turf areas Shrub, flowerbeds and ground covers with Routine, reduce, low and non-irrigated areas Fruit & vegetable gardens Children’s play areas Pet areas Natural areas Non-plant areas

19. Refine the landscape plan Convert bubble areas to a landscape plan.

20. Planning and designing for water conservation, beauty, and utility Take home message:

21. Planning and designing for water conservation, beauty, and utility Take home message It takes planning… water conservation, beauty, and utility does not happen by accident.

22. Selecting plant appropriate for our climate AND Grouping them according to their water needs ( Hydrozoning ) AND Irrigating according to water need

23. Colorado is a semi-arid climate. Select plants suitable to a semi-arid climate. Plant pallet is limited, but not void, without supplemental irrigation.

24. Colorado is a semi-arid climate. Suggested references Xeriscape Plant Guide , by Denver Water, Fulcrum Publishing Xeric Tree and Shrub List by the Community Tree Alliance , CMG Fact Sheet #T15

25. Colorado is a semi-arid climate. On sites, where landscape irrigation is not desirable or possible, focus on natural growth.

26. Hydrozoning Grouping plants according to irrigation needs, AND watering according to need . Routinely irrigated flowerbed Non-irrigated naturalized area

27. Design with irrigation demand in mind. Routine Irrigation Reduced Irrigation Need Limited irrigation once established non-irrigated

28. Design with irrigation demand in mind. Routine Irrigation Reduced Irrigation Need Limited irrigation once established

29. Design with irrigation demand in mind. Garden Routine Irrigation Reduced Irrigation Need Limited irrigation once established

30. Design with irrigation demand in mind. Routine Irrigation Reduced Irrigation Need Limited irrigation once established non-irrigated

31. Hydrozoning myths Xeriscaping is NOT a cacti and rock garden .

32. The objective of hydrozoning is to place low-water requiring plants together in zones that actually receive reduced to no irrigation!

33. Even xeric plant need rain/irrigation during establishment.

34. Water-wise concepts support irrigation for “people space” “ People space” at Thanksgiving Point Gardens

35. Selecting plant appropriate for our climate AND Grouping them according to their water needs ( Hydrozoning ) AND Irrigating according to water need

36. Improving the soil Add organic matter

37. Improving the soil Sandy Soils

38. Improving the soil Sandy Soils Add organic matter

39. Improving the soil Sandy Soils Add organic matter Hold 10+ times more water and nutrients than sand

40. Improving the soil Loam & Clayey Soils

41. Improving the soil Loam & Clayey Soils Add organic matter Prevent compaction

42. Improving the soil Loam & Clayey Soils Add organic matter Prevent compaction  large pore spaces  deep rooting  water supply

43. Improving the soil Exception Some native plants to the high plains and Rocky Mountain region prefer poor soils . In improved soils May thrive, loosing their xeric characteristics Do poorly

44. Factors influencing irrigation management Soil’s water holding capacity Evapotranspiration, ET Rooting depth Plant’s ability to extract water from the soil

45. Water holding capacity Pore spaces Texture and structure Large pore spaces Air Water moves down with gravitational pull Small pore spaces Water Water moves in all directions by capillary action

46. Water holding capacity Saturation Field Capacity Wilting Point

47. Water holding capacity

48. Water holding capacity

49. Evapotranspiration, ET Evapotranspiration, ET , is the rate a crop uses water for transpiration plus evaporation from the soil surface. Factors influencing ET Weather Solar radiation Temperature Wind Humidity Stage of plant growth

50. Evapotranspiration, ET Typical ET for Cool Season Turf* April May June July Aug. Sept. Oct. Per Month 3.98” 4.9” 6.0” 6.5” 5.5” 4.0” 2.8” Per Day 0.13” 0.16” 0.20” 0.21” 0.18” 0.13” 0.09” *Northern Colorado Front Range area

51. Rooting depth and irrigation A deeper rooting system Larger supply of water Go longer between irrigations In compacted or clayey soil Low levels of soil oxygen Limit rooting depth Reducing supply of available water

52. Soil’s water holding capacity + ET + Rooting depth Irrigation management

53. Sandy Loam Sand Loam w/ clay 12” rooting depth Inches available water Amount of water per irrigation 0.5” 0.75” 1” Irrigation summary

54. Sandy Loam Sand Loam w/ clay 12” rooting depth Inches available water Amount of water per irrigation 0.5” 0.75” 1” Days between irrigations April (at 0.13”/day) 4 6 8 July (at 0.20”/day) 2.5 4 5 Irrigation summary

55. Sandy Loam Sand Loam w/ clay 6” rooting depth Inches available water Amount of water per irrigation 0.25” 0.38” 0.5” Irrigation summary

56. Sandy Loam Sand Loam w/ clay 6” rooting depth Inches available water Amount of water per irrigation 0.25” 0.38” 0.5” Days between irrigations April (at 0.13”/day) 2 3 4 July (at 0.20”/day) 1 2 2.5 Irrigation summary

57. Sandy Loam Sand Loam w/ clay 24 inch rooting depth Inches available water Amount of water per irrigation 1” 1.5” 2” Days between irrigations April (at 0.13”/day) 8 11.5 15 July (at 0.20”/day) 5 7.5 10 Irrigation summary

58. Sandy Loam Sand Loam w/ clay 6 inch rooting depth Amount 0.25” 0.38” 0.5” Days 1 2 2.5 12 inch rooting depth Amount 0.5” 0.75” 1” Days 2.5 4 5 24 inch rooting depth Amount 1” 1.5” 2” Days 5 7.5 10 Irrigation summary -- July

59. Factors influencing irrigation demand Soil organic content Organic matter holds 10X more water than sand.

60. Sandy Loam Sand Loam w/ clay 6 inch rooting depth Amount 0.25” 0.38” 0.5” Days 1 2 2.5 12 inch rooting depth Amount 0.5” 0.75” 1” Days 2.5 4 5 24 inch rooting depth Amount 1” 1.5” 2” Days 5 7.5 10 Irrigation summary -- July

61. Factors influencing irrigation demand Irrigation pattern Frequent watering = shallow rooting depth

62. Factors influencing irrigation demand Stage of growth Water use high during blossoming and fruiting

63. Factors influencing irrigation demand Water demand of plants To support growth To survive dry spells

64. Fine-tune the irrigation management

65. Fine-tune the irrigation management In the normal June/July days IF a lawn goes 5 days on 1”

66. Fine-tune the irrigation management In the normal June/July days IF a lawn goes 5 days on 1” Apply 1.0” every 5 days Additional amounts would leach below root zone. 0.8” every 4 days 0.6” every 3 days 0.4” every 2 days 0.2” every day

67. Fine-tune the irrigation management In the normal June/July days IF a lawn goes 4 days on 0.8 ”

68. Fine-tune the irrigation management In the normal June/July days IF a lawn goes 4 days on 0.8 ” Apply 0.8” every 4 days Additional amounts would leach below root zone. 0.6” every 3 days 0.4” every 2 days 0.2” every day

69. Fine-tune the irrigation management In the normal June/July days IF a lawn only goes 2 days on 0.4”

70. Fine-tune the irrigation management In the normal June/July days IF a lawn only goes 2 days on 0.4” Apply 0.4” every 2 days Additional amounts would leach below root zone. 0.2” every day

71. Normal irrigation requirement Cool season turf* April May June July Aug. Sept. Oct. Per week 0.9” 1.1” 1.4” 1.5” 1.2” 0.9” 0.6 ” 7/8” 1 1/8” 1 3/8” 1 1/2” 1 1/4” 7/8” 5/8” * Northern Colorado Front Range area, based on historical ET, normal rainfall and a 70% sprinkler efficiency rating.

72. What do you advise the gardener about, “How much and how often to water the lawn?”

73. Improving the soil Take home message: On sandy soils, O.M improves water holding capacity On clayey soils, O.M. improves soil tilth Deeper rooting depth Greater water supply