Landscape Water Conservation

Xeriscape Landscaping Xeriscape landscaping, quality landscaping that conserves water and protects the environment, is the most exciting concept to hit the landscape industry in decades. The term Xeriscape was coined in Denver, Colorado in 1978. Whether called Xeriscape, water-wise or water-smart landscaping, landscape and water industry professionals throughout the nation have embraced landscape water conservation through education. Xeriscape landscaping incorporates seven basic principles which lead to saving water. By incorporating these seven principles, you can help preserve our most precious natural resource-water. Xeriscape landscapes don’t need to be just cactus and rock gardens. They can be green, cool landscapes full of beautiful plants maintained with water-efficient practices.

1.         Planning and Design: Creating a water-efficient landscape begins with a well-thought-out landscape design. Sketch your yard with locations of existing structures, trees, shrubs and grass areas. Then consider the landscape budget, appearance, function, maintenance and water requirements. Local landscape architects, designers and nurserymen can help in this decision-making. Implementing your landscape design can be done gradually over several years.

2. Soil Analysis: To increase plant health and conserve water, add organic matter to the soil of shrub and flowerbed areas. This increases the soil's ability to absorb and store water in a form available to the plant. As a rule-of-thumb, till in 4 to 6 inches of organic material such as shredded pine bark, peat and rice hulls. For trees, however, incorporating organic matter is not necessary; for large turf grass areas, it is not economically feasible.

3. Plant Selection: Select trees, shrubs and groundcovers based on their adaptability to your region's soil and climate. California is blessed with an abundance of beautiful native plants that are naturally adapted to the region. Most have lower water demands, fewer pest problems and less fertilizer needs than many non-adapted, exotic plants brought into California landscapes. Through the support of the nursery industry, native California plants are becoming more available in retail nurseries and garden centers. Combining California natives with well-adapted exotic plants is a key to a beautiful, interesting landscape that conserves water.

4. Grass Selection: When considering a landscape's water requirement, it is important to note that turf grasses require more frequent watering and maintenance than most other landscape plants. Carefully select grass according to its intended use, planting location and maintenance requirements. Also, when designing or evaluating turfgrass areas in the landscape, consider the ease or difficulty in watering the proposed area. Long narrow areas and small odd-shaped areas are difficult for any irrigation equipment to efficiently water. Try to eliminate long, narrow areas and maintain more blocky, square areas.

5. Landscape Maintenance: An added benefit of Xeriscape landscapes is less maintenance. A well-designed landscape can decrease maintenance by as much as 50 percent through reduced mowing, once-a-year mulching, elimination of weak, un-adapted plants, and more efficient watering techniques.

6. Watering: Of the tremendous amounts of water applied to lawns and gardens, much of it is never absorbed by the plants and put to use. Some water is lost to runoff by being applied too rapidly, and some water evaporates from exposed, un-mulched soil; but, the greatest waste of water is applying too much too often. In addition to over watering plants, excess irrigation can leach nutrients deep into the soil away from plant roots, increasing the chances of polluting groundwater. Similarly, runoff caused by excess irrigation can carry polluting fertilizers and pesticides to streams and lakes. The waste or pollution of high quality water through inefficient irrigation practices can be eliminated through proper watering techniques.

7. Lawns: Most lawns receive twice as much water as they require for a healthy appearance. The key to watering lawns is to apply the water infrequently, yet thoroughly. This creates a deep, well-rooted lawn that efficiently uses water stored in the soil. To know when to water the lawn, simply observe the grass. Wilting and discoloration are signs of water stress. At the first sign of wilting, you have 24 to 48 hours to water before serious injury occurs. Apply 1 inch of water to the lawn as rapidly as possible without runoff. Watering only when needed and watering thoroughly produces a deep-rooted lawn that is more water efficient and drought enduring.

Trees and Shrubs: All trees and shrubs need more frequent watering from planting time until becoming well rooted, which may take two growing seasons. Once established, plants can then be weaned to tolerate less frequent watering. Proper weaning develops deep roots and makes the plants more drought enduring. As with lawns, water established trees, shrubs and groundcovers infrequently, yet thoroughly. In the absence of rain, most trees and shrubs benefit from a once-a-month thorough watering during the growing season. Remember, normal lawn watering is not a substitute for thorough tree and shrub watering. The feeding root system of a tree or shrub is located within the top 12 inches of the soil and at the "dripline" of the plant. The dripline is the area directly below the outermost reaches of the branches. Apply water and fertilizer just inside and a little beyond the dripline, not at the trunk. Simply lay a slowly running hose on the ground and move it around the dripline as each area becomes saturated to a depth of 8 to 10 inches. For large trees, this watering technique may take several hours.

Irrigation Systems: The goal of any irrigation system is to give plants a sufficient amount of water without waste. By zoning an irrigation system, grass areas can be watered separately and more frequently than groundcovers, shrubs and trees. Both sprinkler and drip irrigation can be incorporated to achieve water conservation in the landscape.

Sprinkler Irrigation: Sprinkler irrigation is the most commonly used method of landscape watering. The two most common types of sprinkler irrigation systems are the hose-end sprinkler and the permanent underground system. Even though a permanent sprinkler system can be more water efficient than a hose-end sprinkler, both systems require little maintenance and apply large volumes of water in a short time.

If you have a permanent sprinkler system, make sure the sprinkler heads are adjusted properly to avoid watering sidewalks and driveways. Also, a properly adjusted sprinkler head sprays large droplets of water instead of a fog of fine mist which is more susceptible to evaporation and wind drift. With either hose-end sprinklers or permanent systems, water between late evening and mid-morning to avoid excessive waste through evaporation.

Drip Irrigation: Drip irrigation offers increased watering efficiency and plant performance when compared to sprinkler irrigation. In areas of the state with poor water quality (i.e., high salt content), drip irrigation also allows safer use of "salty water" in the landscape and garden. Drip irrigation slowly applies water to soil. The water flows under low pressure through emitters, bubblers or spray heads placed at each plant. Water applied by drip irrigation has little chance of waste through evaporation or runoff. Seeking professional irrigation advice and experimenting with available drip irrigation products in small sections of the landscape are the best ways to become familiar with the many benefits of this watering technique.

Mulching Conserves Moisture: Mulch is a layer of nonliving material covering the soil surface around plants. Mulches can be organic materials such as pine bark, compost and woodchips, or inorganic materials, such as lava rock, limestone or permeable plastic, not sheet plastic. Use a mulch wherever possible. A good mulch conserves water by significantly reducing moisture evaporation from the soil. Mulch also reduces weed populations, prevents soil compaction and keeps soil temperatures more moderate.

Proper Mowing and Fertilizing Conserves Water: Mowing grass at the proper height conserves water. Mow St. Augustine grass and buffalo grass at 3 inches; for Bermuda grass mow at 1 inch; for centipede grass and Zoysia grass mow at 2 inches. Applying fertilizer to the lawn at the proper time and in the proper amount can save time, effort and money through reduced mowing and watering. Fertilizers also can be a major source of pollution of streams and groundwater if excessive amounts are applied. Fertilize the lawn once in the spring and again in the fall to produce a beautiful turf without excess growth that demands frequent watering. Use a slow-release form of nitrogen in the spring application and a quick-release form in the fall. Apply only 1 pound of actual nitrogen fertilizer per 1,000 square feet of lawn at one time. By using this fertilizer schedule, no other fertilizer is needed to maintain most shrubs and trees in the lawn area.

Other Cultural Practices To Save Water: Other cultural practices that add to the efficient use of water by plants are periodic checks of the irrigation system, properly timed insect and disease control and elimination of water-demanding weeds.

Site Design

· Direct runoff from impervious surfaces (roof or paved areas) to pervious areas (lawns, landscape, etc.)

· Direct gutters and downspouts to landscape areas’ cisterns, or gray water systems.

· Slope driveways, patios and other paved areas to sheet flow on to lawn or other landscape areas.

· Consider green roofs.

Maintenance

· Sweep up driveways, sidewalks and patios instead of hosing them off. This can help conserve downstream water quality.

· Wash your car only when necessary. Use a bucket instead of a constantly running hose. Wash your car in an area that drains to a landscaped area rather than directly to the street or storm drain. Or wash your car at a commercial car wash where water is recycled.

· Recycle pool and spa water by slowly draining to a landscaped area rather than sending it to the sanitary sewer.

· Make sure water is no longer chlorinated when it is drained. Allow enough time for chlorine to break down since the last application.

· Repair leaking fixtures. “A continuous drip from a faucet wastes 20 gallons of water per day.” (EPA)

· Covering your pool when it’s not being used can help conserve water.

· Use automatic shut-off nozzles on your garden hose.

Related links:

http://xeriscape.sustainablesources.com/

http://ndsuext.nodak.edu/extpubs/plantsci/landscap/h957w.htm

http://aggie-horticulture.tamu.edu/aransas/xeriscape.htm

http://www.colostate.edu/Depts/CoopExt/4DMG/Xeris/xeris1.htm