Water Wise Landscaping Rick Durham Department of Horticulture

Average residential water use increases 30% - 50% during the summer months when citizens turn on their outdoor irrigation systems

Water Conservation Measures Summer Surcharge: Rate increases 25% to 100% when use exceeds average winter consumption. Rationing: Odd/Even outdoor watering Bans on Outdoor Use Solution: Economic Incentive + Education

This is equivalent to: 14 five-minute showers 26 runs of the dishwasher 72 flushes of the toilet 9 full loads of laundry One portable lawn sprinkler operating 1 hour uses 360 gallons of water

Coined by Denver Water in 1978, now trademarked From the Greek Word Xeros, which means dry (PronouncedZera-scape)

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

Divide the Landscape into Three Water-use Zones High Water-use Zone (Oasis Zone) Moderate Water-use Zone (Transition Zone) Low Water-use Zone (Xeric Zone)

High Water-use Zone (Oasis Zone) Small high-impact or high visibility area of the landscape where plants are provided their optimum water requirement at all time Entrance to the home or business Annual flowers

Moderate Water-use Zone (Transition Zone) Plants are watered during establishment. Then, once established, they are watered only when they show signs of water stress. Shrubs, dogwoods, redbuds, herbaceous perennials

Low Water-use Zone (Xeric Zone) Once established, plants are provided no supplemental irrigation, except during periods of extreme drought Juniper, Oaks, Maples Viburnums, Ornamental grasses

Goal of Water Wise Landscapes Reduce and minimize the size of the area irrigated and the frequency of irrigation

House Driveway Street EuonymusItea Little Gem Magnolia Native Trees Spirea Native Oak Nandina Turfgrass N

High Water-use Zone ModereLow

Annuals Ornamental Grasses Daffodils/Siberian Iris/Daylilies Mulch Year 1

High Water-use Zone Low Moderate High Year 1

Fescue Liriope Mulch Year 2

Moderate Water-use Zone Low Moderate Low Moderate High Low Year 2

Barberry Purple coneflower Year 3

Moderate Water-use Zone Low Moderate High Low Year 3

Moderate Water-use Zone Low Moderate High Low Year 4

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

Urban soils Often lack topsoil Prone to compaction Organic matter is best remedy –Increases soil structure –Increases porosity and drainage –Increases water holding capacity

How Much Amendment to Use? 25% by Volume 3 inches incorporated to a 12 inch depth 1 cu. yd. / 100 sq. ft. = 3 in. on soil surface 1 cu. yd. = 27 cu. ft. = Nine 3 cu. ft. bags or thirteen 2 cu. ft. bags / 100 sq. ft.

Use only decomposed organic material (right) as a soil amendment

More plants are killed from over-watering than from drought

Possible Solutions to Poorly-drained Soils Plant on raised beds Deep cultivation Install sub-surface drainage Select appropriate plants Possible Solutions to Poorly-drained Soils

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

A few good drought tolerant plants

Annuals

Gazania rigens - Gazania Various colors, most bicolors, full sun 6-10 inches tall Few pests Good drought tolerance Individual flowers are short lived but many flowers on the plant

Gomphrena globosa - Globe Amaranth Purple, orange, lavender, white flowers, full sun inches tall Few pests Used as bedding, border, cut and dried

Helianthus annuus - Sunflower Orange, yellow, bicolors, full sun 2-14 feet tall Powdery mildew is the biggest pest problem Used as border and cut flowers Attractive to butterflies, birds

Melampodium paludosum - Melampodium Yellow flowers, full sun to partial shade inches tall Few pests, occasionally powdery mildew is a problem Used as bedding or border plants May reseed but not invasive

Petunia x hybrida - Petunia Many colors and bicolors, single and double flowers, full sun to part shade inches high, some shorter Few pests Used as bedding and container plants Fertilization and moisture keep them looking good

Portulaca grandiflora - Moss Rose Various colors, full sun 6-10 inches tall Few pests Used in bedding and containers Very heat and drought tolerant

Salvia faranacea - Mealycup Sage Blue or white flowers, full sun inches tall Few pests Used as bedding plants and as dried flowers (calyx)

Zinnia spp. – Profusion Zinnias Pink, orange, white, full sun inches tall Few pest, powdery mildew resistant Used as bedding and container plants A little more expensive but well worth it

Perennials

Achillea - Yarrow Many colors, flower in late spring to summer 2-3 feet tall Few pests Borders, cut flowers, dried Cuttings or division in spring or fall, some by seed

Aquilegia x hybrida - Hybrid Columbine Flower colors, many and bicolors, in spring and early summer 1½ to 3 feet tall Leaf miners may make foliage unattractive Used in borders, will also do well in part shade Division in late summer, seed

Asclepias tuberosa – Butterfly weed Flowers orange in summer 1-2 feet tall Major pest – aphids Used as a border plant and for cut flowers, attractive to butterflies. Propagate by seed or root cuttings, does not transplant well.

Aster spp. - Asters Flowers in blues, violets, whites in summer and fall 1-6 feet tall, taller varieties must be staked Powdery mildew is the major pest Used for borders and cut flowers Propagate by division in spring

Baptisia australis – False indigo Blue flowers in late spring 3-5 feet tall Few pests Used in borders, dried seed pods Division in late fall or early spring, seed

Echinacea purpurea – Purple Coneflower Flowers purple, white in summer to fall 3-5 feet tall Major pest is powdery mildew Used as border or cut flowers Divide clumps in spring or by seed

Hemerocallis hybrids - Daylily Many colors, bloom in early summer 8 inches to 3 feet tall Major pests are aphids and leaf spot Used as border plants or in mass plantings Propagate by division in late summer

Perovskia atriplicifolia - Russian Sage Blue flowers in summer 4-6 feet tall, shrubby Few pests Used as a border Propagate by cuttings, division, or seed

Rudbeckia fulgida - Black-eyed Susan Yellow flowers in summer to fall 2-3 feet tall Powdery mildew is the main pest problem Used as a border, cut or meadow flower Propagation by division or seed

Sedum spectabile - Showy Sedum Pink, red, white, lilac flowers in late summer and early fall inches tall Few pests Used as a border, edging, cut flower or dried Propagation by division or cuttings

Bulbs and other modified stem/root plants

Crocus spp. White, yellow, blue or bicolor flowers in early spring. Some fall blooming species as well 3-5 inches tall Few pests Used as borders Propagate by offsets Not a true bulb - corm

Iris hybrids - Tall Bearded Iris Various colors and bicolors in late spring 2-4 feet tall Main pest is iris borer Used in borders Propagate by division in fall Not a true bulb - rhizome

Muscari armeniacum - Grape Hyacinth Blue and white flowers in spring 4-8 inches tall Few pests Used in borders and as cut flowers Propagate by offsets

Narcissus spp. and hybrids - Daffodil Yellow, white and pink, single and double flowers in spring 3-18 inches tall Few pests Used as border and cut flowers, also containers Propagate by offsets and division

Wildflowers, especially spring ephemerals Ornamental grasses Culinary herbs Most food crops (vegetables and fruits) need plentiful moisture Also consider:

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

Use Turfgrass for a Purpose Aesthetic Value (Welcome Mat) Recreational Surface Erosion Control Minimize the amount of irrigated turfgrass

Avoid Using Irrigated Turfgrass Just to Fill Space

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

Drip Irrigation Uses 30% to 50% less water than sprinkler irrigation Avoids spraying foliage so diseases are less likely to occur No spray drift Only need to water 25% of the root area

Reducing Reliance on Municipal Water Supplies Through Rainwater Harvesting

Roof Catchment Potential Sq. ft. X catchment coef. X no. gal./cu. ft. area X feet rainfall sq. ft. X 0.95 X 7.48 X (1/4 in. rainfall) Catchment Potential Per 2,500 sq. ft. of roof area ¼ rainfall369.5 gallons ½ rainfall740.8 gallons ¾ rainfall gallons 1 rainfall gallons

Irrigation Needs ½ acre lot: 21,780 sq. ft., 10% ½ /1,000 sq. ft sq. 300 gal./1000 sq. ft. = 653 gallons/wk Another 10% of the landscape drip irrigated 50 drip 1 gal./hr.: run 6 hours = 350 gallons/wk Need 653 gal gal. = 1,003 gal./wk. Or 4,013 gallons to get you through a 4 wk drought

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

Best Mulch OrganicFine-texturedNon-matting

Newspaper placed under mulch, 2- to 3-sheets thick, helps provide an added barrier to moisture loss.

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

When Managing a Water Wise Landscape, Avoid Frequent Flushes of Vegetative Growth Brought on by: Fertilization Pruning Irrigation

Fertilization Target fertilization to plants that need it. Established trees and shrubs may not need to be fertilized annually. Use slow-release forms of nitrogen Use low rates of fertilizer Limit fertilization during dry periods

Too Much Nitrogen Increases pest problems Increases top growth Reduces root growth Increases pruning requirements Increases run-off into groundwater

Prune by selective thinning instead of shearing

Grasscycling Let the Clips Fall Where they May Clippings Add Nitrogen Back to the Soil Clippings Help Hold Moisture in the soil Clippings DO NOT Cause Thatch

Seven Steps of Xeriscape Planning and Design Soil Analysis Appropriate Plant Selection Practical Turf Areas Efficient Irrigation Use of Mulches Appropriate Maintenance

Acknowledgements Dr. Gary Wade University of Georgia Department of Horticulture