Xeriscape
California has always had water shortages.The booming population
increases demand on the limited supplies more every
year. Roughly 50 percent of our domestic water use is outside the
house. Urban water demands are highest during the summer and lowest
during the winter -the inverse of natural runoff patterns. Landscape
irrigation is the primary water user outdoors in urban areas. Much
of this water is used to maintain traditionally high water-demanding
landscapes, or it is applied inefficiently. To reduce excessive
water, use Xeriscape - landscaping that conserves water and protects
the environment. Xeriscape landscaping incorporates seven basic
principles to save water:
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. Then consider the landscape budget, appearance,
function, maintenance and water requirements. Local landscape architects,
designers, nurserymen and county Extension agents can help. 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 flower beds. This increases the soil's ability to absorb and store water in a form available to plants. As a rule-of-thumb, till in 4 to 6 inches of organic material such as shredded pine bark, peat and rice hulls.
3. Practical turf areas
When
considering a landscape's water requirement, it is important to
note that turfgrasses require more frequent watering and maintenance
than other landscape plants. Carefully select grass according to
its intended use, planting location and maintenance requirements.
Achieving a significant reduction in water consumption and landscape
maintenance may involve reducing the size of water-sensitive lawns
through the use of patios, decks, shrub beds and groundcovers.
When designing turfgrass areas in the landscape, consider the ease
in watering the proposed area. Long narrow areas and small odd-shaped
areas are difficult to efficiently water.
4. Plant Selection
Select
trees, shrubs and groundcovers based on their adaptability to our
region's soil and climate. We are 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 exotic plants. Check with your local nursery or county Extension
agent for recommendations on adapted landscape plants for your area.
5. Efficient irrigation
Of the tremendous amounts of water applied to lawns and gardens, much of it is never absorbed by the plants. Some water is lost to runoff by being applied too rapidly, and some water evaporates from exposed soil but the greatest waste of water is applying too much too often.
In addition to overwatering the plants, excess irrigation leaches nutrients deep into the soil away from plant roots, increasing the chances of polluting groundwater. Runoff caused by excess irrigation carries polluting fertilizers and pesticides to streams and lakes. 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, 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 injury occurs. Apply 1 inch of water to the lawn as rapidly as possible without runoff.
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. 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 at the "dripline" of the plant - 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 until the soil saturated to a depth of 8 to 10 inches. For large trees, this watering may take several hours.
6. Use of Mulch
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.
7. Landscape Maintenance
An added benefit of Xeriscape landscapes is less maintenance. A
well-designed landscape can decrease maintenance by 50 percent through
reduced mowing; once-a-year mulching; elimination of weak, exotic
plants; and more efficient watering techniques.
Mowing grass at the proper height conserves water. Mow St. Augustinegrass and buffalograss at 3 inches; for Bermudagrass mow at 1 inch; for centipedegrass and Zoysiagrass 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. Fertilize the lawn once in the spring and again in the fall to produce a beautiful turf without excess growth. 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.
Conclusion
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.
