Landscape Planning and Design
A WaterWise landscape doesn't just happen. It is intentionally designed to enhance the natural space with minimal environmental impact. Texas AgriLife Extension Service has an extensive program called EARTH-KINDTM that takes into account many factors in addition to water use. For more about that program, visit their Web site:
A design may be sketched on a napkin or plotted on an expensive
CAD system, but it must be on paper or electronic devise so it can be discussed
and evaluated. A WaterWise design takes into account the seven principles of
a water efficient landscape. The design should include an estimate of supplemental
water needed to support the plant material in normal times, and to keep it
alive in times of drought. This estimate gives the property manager a way to
evaluate maintenance activities and the water purveyor an opportunity to establish
guidelines for landscape water use in the area.
The structure, composition, and prior cropping patterns of the soil in the landscape
greatly influences the way it must be managed for proper landscape establishment.
It is important to have the soil tested to assess a starting point for soil management.
For more about soil tests visit the TAMU soil testing lab Web site:
Plants used in the plan should be suited to the native soil and soil should be
of sufficient depth to support the selected plant material. Because soil types
may vary widely even within the same city, a soil test is essential before plant
selection begins. While soils may be amended to accommodate specific plant material,
the best plan is to put the plants in place that are best adapted to the native
soil. In the case of a new subdivision, native soil may have been displaced and
soil tests are necessary to evaluate the condition of the remaining topsoil.
A minimum of eight inches of soil is recommended for turf. Soil requirements
of the plant material most commonly available in Texas can be found in the PlantSelector
section of this web site.
Land contours dictate drainage. The landscape should be shown to prevent unwanted
overflow into the residence, nearby residences, or into the street. Runoff from
buildings should be channeled into plant material to clean water before moving
it into storm drains. Advanced design would allow runoff from building roofs
to be captured for use in landscape irrigation.
Thirsty plant material should be placed at the bottom of hills. On a large lot
or commercial campus, areas close to the buildings may be designed for more intensive
care while areas in outlying space are left more natural requiring little or
no supplemental irrigation. Irrigation requirements of plant material most commonly
available in Texas can be found in the PlantSelector section of this Web site.
Hardscape can be used in areas not amenable to plant material. Potential runoff
from hardscape should be taken into consideration. Ponds, swales, berms, and
rain gardens should be used to manage water flow. Hardscape decorative mulch
should be used in narrow or odd shaped areas to avoid watering overspray.
Rain catchment for reuse in the landscape is an advanced practice that adds greatly
to the water efficiency of a landscape during times of normal rainfall.
Irrigation system design should be done in conjunction with landscape design
and plans should be reviewed by the same entity at the same time. Construction
schedules require that all review of landscape plans be carried out in an efficient
and scheduled manner since the landscape and irrigation systems are often installed
during construction, particularly in new subdivisions.
Treatment of slopes. Plant selection criteria include use of groundcover or other
erosion-prevention such as compost in place of turf on slopes greater than.
Designs should indicate a range of plants for specific areas rather than narrow
specification due to the fluctuations in plant availability. A landscape contractor
may be able to get a plant with the same characteristics, but not a specific
plant, according to stringent scheduling.
"Landscape planning and design is essential to water use efficiency..."|
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