The first step in planning a water-efficient landscape is the process of the site analysis (Kelly, et al., 1991) One of the most important steps is to plan your landscape design. First assess the topography and determine drainage patterns. Examine your site conditions and pinpoint both shady and sunny areas. Decide whether any of the existing vegetation should be preserved. A base map is a plan of the property drawn to scale on graph paper showing the location of the house, its orientation to the sun, other structures on the site, unusual features such as stone outcroppings and existing vegetation (Wade et al., 2002).
To begin your plan, overlay the base map and site analysis sheet with another piece of tracing paper. On this sheet indicate the public, private and service areas of your landscape. Consider how these areas will be developed based on space requirements for each activity. The public area is the highly visible area that most visitors see, such as the entry to the home. In a traditional landscape, this area typically receives the most care, including the most water. Therefore, the careful design of this area is important for water conservation. This area can be designed to require minimal water and maintenance without sacrificing quality or appearance. The private area of the landscape, usually the backyard, is where most outdoor activity occurs. It is generally the family gathering area. It may also include a vegetable garden or fruit orchard. The landscape in this area needs to be functional, attractive and durable, but it also should be designed to require less water than the public area of the landscape. The service area is the working or utility area of the landscape, an area usually screened from view and containing such items as garbage cans, outdoor equipment, air-conditioning units or a doghouse. In terms of routine maintenance, this area would be designed to require the least care and water of the three areas. In addition to dividing the landscape into use areas, a Xeriscape plan further divides the landscape into three water-use zones: high (regular watering), moderate (occasional watering) and low (natural rainfall) (Wade et al., 2002). To incorporate Xeriscape concepts into your design, some additional thought is needed. The information you generate by drawing a plot plan and doing a site analysis should be integrated to identify microclimates in your yard. Microclimates are created by differing physical and environmental conditions within the landscape. Moisture, sun, shade, air movement, and heat all contribute to create zones that have varying water requirements (Welsh, 2000).
High water-use zones
Very low water zones are of two kinds. Decks and paved areas require no water. These areas help provide recreational and living space and are very practical. However, for paved areas, you should consider using permeable materials such as bricks or paving stones rather than concrete or asphalt to encourage rain to soak into the ground rather than run off. Protected areas where the exposure and shade conditions work together to inhibit evaporation are also very low water-use zones. In these areas, irrigation is needed only to establish new plants. Existing, well-established vegetation in these zones should be retained and new vegetation should be selected on the basis of minimal water use. Because very low water zones require little or no irrigation once they’re established, they offer the greatest potential for saving water. Such shaded areas not only reduce water demand, they can also lower indoor temperatures and reduce summer cooling bills.
Low water-use zones
Low water zones are somewhat exposed areas that must be watered to keep plants flourishing but where water can be conserved by mulching and using an efficient low – volume irrigation system or by taking advantage of runoff from downspouts, driveways or patios.
Moderate water-use zones
Moderate water zones are exposed areas with turf or plants with higher water requirements. This zone should be kept small and should be limited to focal points, such as entrance areas, and functional areas, such as lawns. Identifying water-use zones in your yard helps you to group plants with similar water needs together for watering efficiency.
