Xeriscape - landscaping for water conservation

June 10, 2004
DONNA ROBERTS
Victoria County Master Gardener

With the temperatures in the mid-90s since the recent holiday weekend, everything has been in need of more water. Parched plants and human dehydration are real possibilities as summer gets hotter and hotter.

We all know that water is an essential element of life - and we have become even more aware of this concept recently with all of the news in our local media about the water issue. We all have assumed that there will always be an adequate supply of water to meet our needs; however, we only have to look at drought-stricken areas in our own state and country to discover the fallacy of this belief.

The percentages differ from region to region, but according to recent statistics, about 25 percent of the water used in urban areas is applied to landscapes and gardens. Most of this water is lost to runoff by being applied too rapidly, or lost to evaporation due to the time of day it is applied and/or being applied to unmulched soil.

The greatest waste of water is applying too much, too often. In addition to wasting water, excess irrigation can leach nutrients deep into the soil away from plant roots and increase the chances of polluting groundwater. Runoff caused by excess irrigation can also carry polluting fertilizers and pesticides to streams and lakes. This waste and pollution of water through inefficient irrigation practices can be eliminated through proper water techniques.

To promote environmental awareness, Texas Cooperative Extension implemented the Earth Kind gardening program. This program combines the best organic and traditional gardening principles to create a new horticultural system for the future. Scientific studies show that by faithfully using Earth Kind gardening and landscaping techniques, you can enjoy success with your plants and protect our fragile environment. There is no magic, no miracle product, no secret formula involved; it is just sound, workable technology that can be easily understood and explained.

Much of the Earth Kind gardening program involves the principles of xeriscape gardening. Xeriscape is an innovative, comprehensive approach to landscaping for water conservation. Traditional landscapes may incorporate one or two principles of water conservation, but the total xeriscape concept is seldom employed to effectively reduce water waste.

Xeriscape landscaping incorporates seven basic principles that can help preserve our most precious natural resource - water. The principles of xeriscape landscaping are the standards for conserving water in the landscape; however, the principles are also applicable in the vegetable garden and fruit orchard. These principles are:

· Good design.

· Soil analysis.

· Practical turf areas.

· Appropriate plant selection.

· Efficient irrigation.

· Use of mulches.

· Appropriate maintenance.

A good design addresses the water needs of a site and what water resources may already be available, such as low areas where water collects. A good design combines the plants' needs with the climate of the site. Analysis shows improvement of soils with rich organic matter helps to hold more moisture for plants and allows the excess water to drain freely. No single turf species is suitable for all conditions throughout Texas; however, there are some varieties that are better suited for our area. Your local nursery or extension agent can give you the names of those varieties.

Using plants adapted to the area reduces water use and can greatly reduce the need for insect and disease control. To conserve water even more efficiently, it is important to group plants with similar water needs, and water accordingly. Learning how to water efficiently may be the most effective way to reduce landscape water-waste.

Efficient watering depends partly on equipment used. The most efficient system is a hybrid that includes pop-up sprays or subsurface drip for turf and groundcover, bubblers for trees and planters, and low-volume equipment (drip and micro-sprinklers for shrubs.)

Water on an infrequent, as-needed basis and use enough to soak the top 6 to 8 inches of soil. Water during the early morning hours when the least amount will be lost to evaporation from heat or wind. Watering in the evenings is NOT advised as it increases the chance for diseases and pests.

Mulch provides a protective cover for the soil and plant roots. It moderates soil temperature extremes, retains soil moisture and discourages soilborne plant diseases. An adequate layer of mulch also keeps weed populations suppressed.

Now, I know some of you by now are wondering about plant selection. Plant selection is one of the most important parts of xeriscape landscaping. Categories that include xeriscape plants are as follows: vines, groundcover, ornamental grasses, perennials, dwarf shrubs (1 to 3 feet), small shrubs (3 to 5 feet), medium shrubs (6 to 9 feet), large shrubs (10 to 25 feet), small trees (20 to 35 feet), and large trees (35 feet and up).

For the sake of room for this article, I am only going to list the plants under each category that are native Texas plants. If you want a list of more varieties (and there are many more), contact me at the master gardener address, and I will be glad to get you a list of other plants in each category. Texas native plants from the Xeriscape plant list are as follows: coral honeysuckle, trumpet vine, Virginia creeper, fountain grass, salvia greggii, butterfly weed, rudbeckia, Indian blanket, purple coneflower, dwarf buford holly, dwarf yaupon holly, Turk's cap, beautyberry, Texas sage, red bud, Mexican buckeye, Texas mountain laurel, lacey oak, bald cypress, live oak, and pecan.

Working with xeriscape landscaping plants not only is better for our environment but also requires a lot less time and maintenance on our part - and I don't know about you, but having a little more free time to enjoy my landscape instead of working in it sounds good to me! Local nurseries all carry xeriscape plants - and what they don't have on hand, they can order for you.

Now sit back and enjoy the beauty of your xeriscape landscape while helping conserve our precious commodity of water.