Landscape Water Conservation...
Xeriscape TM
Douglas F. Welsh, Extension Horticulturist
William C. Welch, Extension Landscape Horticulturist
Richard L. Duble, Extension Turfgrass Specialist (retired)
Texas Agricultural Extension Service
An adequate supply of high quality water has become a critical
issue for the future prosperity of Texas. Booming populations have
increased the demand on the state's already limited supply of high
quality water. In addition, seasonal fluctuations in rainfall and
periodic droughts have created a feast-to-famine cycle in Texas.
In urban areas of Texas about 25 percent of the water supply is
used for landscape and garden watering. Much of this water is used to
maintain traditionally high water-demanding landscapes, or it is
simply applied inefficiently.
In an attempt to reduce the excessive water use, the Texas
Agricultural Extension Service is educating Texans in Xeriscape
landscaping, quality landscaping that conserves water and protects the
environment. This concept is a first-of-a-kind, comprehensive approach
to landscaping for water conservation. Traditional landscapes may
incorporate one or two principles of water conservation, but they do
not utilize the entire concept to reduce landscape water use
effectively.
Xeriscape landscaping incorporates seven basic principles which
lead to saving water:
- Planning and design
- Soil analysis
- Practical turf areas
- Appropriate plant selection
- Efficient irrigation
- Use of mulches
- Appropriate maintenance
By incorporating these seven principles, you can help preserve our
most precious natural resource-water.
Xeriscape landscapes need not be cactus and rock gardens. They can
be green, cool landscapes full of beautiful plants maintained with
water-efficient practices. The same green Texas-style landscape which
we are accustomed to can be achieved and still conserve water.
Start With a Plan
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, nurserymen and county Extension
agents can help in this decision making. Implementing your landscape
design can be done gradually over several years.
Soil Analysis and Preparation
To increase plant health and conserve water, add organic matter to
the soil of shrub and flower bed 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 turfgrass
areas, it is not economically feasible.
Plant Selection
Select trees, shrubs and groundcovers based on their adaptability
to your region's soil and climate. Texas is blessed with an abundance
of beautiful native plants which are naturally adapted to the region.
Most have lower water demands, fewer pest problems and less fertilizer
needs than many nonadapted, exotic plants brought into Texas
landscapes.
Through the support of the nursery industry, native Texas plants
are becoming more available in retail nurseries and garden centers.
Combining Texas natives with well-adapted exotic plants is a key to a
beautiful, interesting landscape which conserves water. Refer to the
tables in this publications, and check with your local nursery or
county Extension agent for recommendations on adapted landscape plants
for your area.
- Outstanding Landscape Plants for Texas Xeriscapes
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Grasses
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Vines and Groundcovers
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Perennials
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Shrubs
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Trees
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Water-Saving Native Plants
Grass Selection
When considering a landscape's water requirement, it is important
to note that turfgrasses require more frequent watering and
maintenance than most other landscape plants. Carefully select grass
according to its intended use, planting location and maintenance
requirements.
St. Augustinegrass and bermudagrass are most often used for lawns
in Texas. Zoysiagrass, buffalograss and centipedegrass are used less
often but offer much promise for landscape water conservation.
Grasses available for use in Texas lawns vary significantly in
water requirements. Planting the lowest water use turfgrass adapted to
the region is an effective way to reduce landscape irrigation
requirements.
Achieving a significant reduction in water consumption and
landscape maintenance may also involve reducing the size of
water-sensitive lawns through the use of patios, decks, shrub beds and
groundcovers.
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.
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, unadapted plants; and more efficient watering techniques.
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, unmulched soil; but, the greatest waste of
water is applying too much too often.
In addition to overwatering the plant, 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.
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 which 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.
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. 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 which 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.
Water Conservation Commitment
For each person in Texas, water must always be a vital concern.
Water is a limited and fragile resource. The water used to irrigate
landscapes is considered a luxury use of water by many people.
Nonessential use of water implies a special responsibility to
efficiently use the resource and to protect its quality.
Water conservation in the landscape does not mean planting a harsh
cactus and rock garden. It means common sense landscaping to protect
water quality and quantity. It also means following the principles of
water conservation to insure continued prosperity for the residents
and businesses of Texas.
By following these guidelines and tips, you can proudly create your
own Xeriscape landscape.
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.
Texas has more than 20 educational projects currently active.
Demonstration gardens and tours, seminars, television programs and
design contests are just a few of the methods used to make the
Xeriscape concept familiar throughout Texas and the nation.
The seven principles of Xeriscape landscaping are not new; they
have been practiced in the landscape industry for decades. The concept
of combining all seven guidelines into one effort toward landscape
water conservation is what makes Xeriscape landscaping unique. The
principles are given below:
| 1. Planning and design is the foundation of
any water-wise landscape. |
 |
| 2. Soil analysis will determine whether soil
improvement is needed for better water absorption and improved
water-holding capacity. |
 |
| 3. Practical turf areas suggests that turfgrasses be
used as a planned element in the landscape. Avoid impractical turf
use, such as long, narrow areas. |
 |
| 4. Appropriate plant selection keeps the landscape more
in tune with the natural environment. Both native and exotic
plants make up the huge variety of plants available for Xeriscape
landscaping. |
 |
| 5. By simply using efficient irrigation, you can
instantly save 30 to 50 percent on your water bill. |
 |
| 6. Use mulches in flower and shrub beds to prevent
water loss from the soil through evaporation and to increase water
penetration during irrigations. |
 |
| 7. Appropriate maintenance preserves the beauty of the
Xeriscape landscape plus saves water. Pruning, weeding, proper
fertilization, pest control and irrigation system adjustments all
conserve water. |
 |
. . . seven simple steps to landscape water conservation. Join
the Xeriscape movement. Check with your local water department or
county Extension agent for more information.
Xeriscape and the Xeriscape logo are trademarks of
the Denver Water Department.
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