Xeriscaping: Retrofit Your Yard - Colorado State University

Xeriscaping: Retrofit Your Yard - Colorado State University

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  Xeriscaping: Retrofit YourYard Fact Sheet No. 7.234 Gardening Series| Basics by C.R. Wilson and A. Cummins* The average home landscape uses as much away so water doesn’t wet fences, or switch to Quick Facts as 50 percent of the water in a household. drip (micro-irrigation). Even if you already have a well-established Steep slopes, especially those on south • As much as 50 percent of landscape, you can substantially reduce water and west exposures, waste water through household water is used for use by following some simple steps. runoff and evaporation. Utilizing or installing the yard and garden. a control timer that allows for cycle and soak irrigation may solve the problem on gentle • Change turf areas on steep Survey Your Yard slopes. Another idea is to convert these areas slopes, hard-to-water places Observe turf grass areas that are to perennials or ground covers that tolerate and narrow mowing strips to difficult to water and maintain. These the exposure and thrive on little water. They low-water ground covers. include: also are easier to maintain because unsafe • Use or update an irrigation • along fences; mowing on steep slopes can be eliminated. • on steep slopes where water tends to controller for cycle and soak Drip (micro-irrigation) that slowly applies run off; water over longer periods of time may further irrigation to minimize runoff • corners of lawns where it is hard to water minimize runoff. Another option to consider from slopes and compacted without overlapping into other areas; is terracing. Note that landscape berms soils • narrow strips of lawn between the house where soil is deliberately mounded also waste • Modify sprinkler systems and sidewalk or driveway; and water from sprinkler runoff. Drip (micro- to water only turf areas, not • irregularly shaped lawn areas that do not irrigation) is a better way to irrigate berms. fit the normal pattern of most sprinklers. hardscapes. Strips narrower than 8 feet are difficult If you have an underground sprinkler to irrigate effectively. Size areas accordingly. • A low pressure, micro- system, turn it on and observe where the Irregularly shaped areas should be re-shaped irrigation (drip) system can water sprays. Better yet, place shallow to fit sprinkler irrigation patterns and odd- save water. containers, such as plastic margarine tubs or shaped areas converted to drip irrigated, xeric metal coffee cans, in various locations and plantings or hardscape. • Like any plants, xeric plants measure the water depth after 10 minutes. Study the highly trafficked areas in your require more water for If some areas don’t receive as much water as yard including play areas for children and establishment. others, your sprinkler system may require exercise areas for pets. These areas are best maintenance or renovation to water the left in turfgrasses that can take the wear. landscape evenly without wasting water. Note that bluegrass is one of the best-adapted Common sprinkler system problems include grasses for wear tolerance. Xeric grasses such mismatched nozzles or spray and rotor as buffalograss have less wear tolerance partly heads installed on the same zone. (For more because they grow slowly on less water and information see fact sheet 7.239, Operating don’t replace worn-off grass. Other areas, and Maintaining a Home Irrigation System.) however, can be converted to shrub borders, Adjust heads that are spraying concrete flower gardens and non-turf ground covers and other hardscape surfaces to water only that use less water. Designated paths of worn plants. Sprinklers spraying wood fences turf may be altered to stepping stones or cause unsightly water staining and rapid flagstones, perhaps with a dwarf groundcover deterioration thus increasing financial costs. planted among the stones. Relocate sprinkler heads near fences so water Look for lawn areas that do poorly sprays towards plants, move heads further because of heavy shade from trees or © Colorado State University structures. Rather than keep these areas Extension. 3/96. Revised 8/11. in bluegrass, plant shade-tolerant fine www.ext.colostate.edu * C.R. Wilson, Colorado State University Extension fescue grass or alternative ground covers horticulture agent, Denver County; A. Cummins, Colorado that tolerate shade and mulch them. If the State University Extension horticulture agent, Douglas County. 8/2011
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  location is appropriate,install a patio or Table 1: Low ground covers for hot, steep slopes. raised deck. Scientific Name Common Name Note that turf does play an important Achillea tomentosa Wooly yarrow role in the landscape when placed in well Artemisia schmidtiana ‘Silver Mound’ Silver mound sage thought out locations. Turf prevents soil Buchloe dactyloides Buffalograss from moving into the air, streams and homes. Turf is the best filter of runoff and Callirhoe involucrata Prairie winecups scrubs pollutants from water. It builds Calylophus serrulatus ’Prairie Lode’ Prairie Lode sundrops soil for other plants and is one of the best *Cerastium tomentosum Snow-in-summer means of urban fire control. Delosperma species Ice plant Eriogonum umbellatum var. aureum 'Psdowns' KANNAH CREEK® buckwheat Removing Turf #Gazania linearis COLORADO GOLD® Colorado Gold® gazania Mark off unwanted turf areas with a Juniperus horizontalis Creeping juniper string and stakes or a garden hose. Do not Juniperus sabina ‘Buffalo’ Buffalo juniper leave sharp angles or small strips that are Nepeta 'Psfike' PP 18,904 Little Trudy® catnip difficult to water without overlapping into Oenothera missouriensis Ozark primrose nonturf areas. Penstemon caespitosus Creeping or mat penstemon Modify your sprinkling system so water is applied only to the turf you retain. Penstemon linarioides var. coloradoensis Silverton bluemat penstemon In some cases, this may involve changing Phlox subulata Creeping phlox the spray patterns of the heads from a full Sedum species Stonecrop circle to a partial circle. In other cases, it Stachys byzantina Lamb's ear may require reorienting heads to direct Thymus species Thyme water away from the nonturf areas. Major Veronica pectinata Wooly speedwell changes, however, may require shutting off parts of zones and relocation or installation Veronica prostrata Prostrate speedwell of complete sprinkler lines. Veronica liwanensis Turkish veronica Another method is to let the sprinkler Zauschneria garrettii ORANGE CARPET® Hummingbird trumpet pattern be your guide and renovate areas *Zinnia grandiflora Prairie zinnia not covered by the spray pattern. *Invasive if kept too moist. # Self seeds. It is not necessary to strip unwanted sod. An easier method is to apply Table 2: Plants for narrow planting strips. glyphosate (sold as Roundup, Kleenup, Kill Zall, Com Pleet) to actively-growing grass. Use any of the ground covers in Table 1 between walks and buildings or on parking strips between sidewalks and curbs, unless shaded. If the area is shaded, use one or more of the Use a spade to cut a slit between turf you following: want to save and that to be killed. Severing Scientific Name Common Name underground roots avoids movement *Aegopodium podagraria variegatum Bishop’s weed of herbicide spray via the roots to turf designated for retention. Arctostaphylus x coloradoensis Panchito manzanita Glyphosate must be applied carefully, *Campanula carpatica Carpathian harebell because even the slightest drift onto *Ceratostigma plumbaginoides Plumbago adjoining grass or other nontarget plants *Convallaria majalis Lily-of-the-valley will damage them. Use a low-pressure, Euonymus fortunei 'Coloratus' Wintercreeper coarse-droplet spray with a handheld, *Galium odoratum Sweet woodruff cardboard or metal spray shield. Better yet, consider a wick-type applicator available at Geranium sanguineum Bloody cranesbill many garden centers. Apply only when you Mahonia repens Creeping grape holly are certain it will not rain for at least eight Polygonum affine ‘Border Jewell’ Border Jewell polygonum hours after application. Wait seven to ten Thymus pseudolanuginosus Wooly thyme days, then plant alternative ground covers, Vinca minor Periwinkle shrubs or flowers. #Viola corsica Corsican violet Another way to kill grass is to overlap black and white newsprint on the lawn you *Invasive if kept too moist. # Self seeds. want to kill. Lay the newspaper on the grass in overlapping sections at least 10 sheets companies. Sprinkle the chips with water to begin to decompose, creating extra organic thick. Weigh it down with 4 inches of wood settle them and keep them from blowing. matter that is beneficial to the soil. chips to keep it from blowing. You usually The newspaper and wood-chip mulch In areas where you plan to use mulches can purchase wood chips from tree service smothers the grass. After a few weeks the or you are going to plant on a steep slope, grass will be dead and the newspaper will leave the killed grass in place. The dead
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  grass and itsroots and runners help reduce is best done by hand. Once the soil has soil erosion until the new planting is settled around new plants, the drip system established. To improve appearance and can maintain moisture. (See 4.702, Drip reduce future weed growth, cover the dead Irrigation for Home Gardens.) grass with about 4 inches of mulch, such as wood chips or bark chunks. Spot treat with glyphosate any grass and weeds that Practices to Avoid sprout through the mulch. As the dead Do not group plants with different water grass decays, it contributes organic matter needs together in the same irrigation zone. to the soil. You will not be able to meet the water needs Where you want flower beds, it is best of any of the plants resulting in poor plant to till under the dead grass. Any glyphosate growth or death. A common mistake is residue that comes into contact with soil to group a high water use plant such as a will be deactivated and will not harm new spruce together with a low water use pine. plantings, except where direct seeding “Hydrozone” plants by grouping plants with is done. similar water needs together so they can be If you seed flowers, alternative grasses effectively watered for best plant health. and vegetables, remove the dead grass and When removing areas from turf, do roots. Residue in the dead plant material not cover them with solid sheet plastic and can interfere with seed germination. An gravel, rock or volcanic cinder. Plastics alternative is to thoroughly rototill the dead shed water and create wasteful runoff. They grass into the soil and wait until the grass exclude water and essential air exchange has fully decomposed. If kept moist (but to plant roots, increase evaporation from not wet), this may take one month to six surrounding areas by raising local soil and weeks in warm weather. air temperatures, and can cause root injury Note that xeric plants are similar to high due to heat buildup. water use plants during establishment. They Keep rock or gravel areas to a require regular and relatively high amounts minimum. They tend to increase air and of water after transplanting or seeding. soil temperature. Use weed barrier fabrics Only after xeric plants are well established (geotextiles) available in garden centers. can they be gradually weaned and watered These materials allow water penetration more sparingly. Consider water availability and air exchange. Cover landscape fabrics when deciding the timing of a change from with mulch. a moderate or high water using landscape Instead of rock and gravel, consider to a xeriscape. organic materials such as wood chips and chunk bark. They give a natural look and help retain moisture, as well as hold weeds Drip (micro-irrigation) in check. Use mulch either with or without Systems a landscape fabric to save water. Drip or micro-irrigation systems can Rock may be required to cover a steep be a good way to water any type of plant slope where wood chips and gravel may except turf. Low pressure, micro-irrigation wash away. In these cases, use natural river systems apply water slowly and close to the bed cobble of varying sizes. Lay rock over a ground. This eliminates waste from water weed barrier fabric in much the same way blowing off-target and reduces water use. as if you were constructing a rock wall. The boundary between sprinklers and drip Another option for steep slopes is irrigation has blurred with advancements to install a natural rock garden with in micro-irrigation to include spray stakes. water-conserving alpine plants. For more Most micro-irrigation systems are easy to information, see 7.401, Rock Gardens. install and modify. Drip irrigation kits are Terracing steep slopes is another option to available at most garden centers. They allow consider. you to water plants separately with emitters, or water groups of plants with micro-spray stakes or tapes that ooze water along their entire length. You can enlarge the system as plants grow or as new plants are added. Colorado State University, U.S. Department of Use drip systems to maintain constant Agriculture and Colorado counties cooperating. moisture in the plant root zone. Do not CSU Extension programs are available to all without discrimination. No endorsement of products mentioned use them to “water in” new plantings. New is intended nor is criticism implied of products not plantings need rapid, deep watering that mentioned.