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
- Grasses
- Vines and Groundcovers
- Perenials
- Shrubs
- Trees
- 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.
Hypertext markup by Gretchen Eagle and Dan Lineberger.
http://aggie-horticulture.tamu.edu/extension/xeriscape/xeriscape.html
Revised 26 October 2000
