The high desert is a land of stunning beauty and contrast, but its climate of extremes presents a few challenges to the home gardener. Fortunately, these can be overcome with careful analysis and thoughtful planning. Plants are adapted to specific microclimates, many of which can be found close together in the high desert. For example, a sheltered, northern exposure will support plants that would perish if planted in a dry, sunny, windswept spot, and vice versa. Site analysis and site-specific design are the key to high desert gardening success.
Examine your site and determine which side of your house faces north. Make a note of which areas are sheltered and which are exposed to sun and winds. Look for low, shaded spots which will be cooler and moister in summer but may stay colder in winter.
Measure your site using a 100-foot or longer measuring tape. Begin your measurements from building corners and try to stay at a 90-degree angle from the wall faces. Have a partner help you with this by writing down the measurements directly onto a rough sketch of the site drawn on graph paper. Be sure to make a note of any easements, existing features and existing plants you want to keep.
Decide how many feet each square on the graph paper should represent so that your entire site will fit on a single page. For small lots this may only be 1 foot, but larger lots may require that you make each square 5 or more feet. Draw your site to scale on the paper and fill in any important features such as power lines, driveways, buried utilities or septic tanks.
Analyze this base drawing to define your site's microclimates. Determine the best locations for tender plants, and spots where only the hardiest plants can grow. Remember that in high desert locations, one site will typically have several microclimates.
Select plants you like that are adapted to each specific microclimate and find out how large they will be at maturity. Use the drawing pencil to draw circles roughly the mature width of the plant and experiment until you can fit them into the most appropriate spaces, remembering to leave room for paths and for maintenance access around buildings. Think in terms of drifts and clumps of plants, rather than individual specimens. Group at least five to seven of the same shrub or perennial with together. Place plants with similar water needs in the same beds.
Review your preliminary design to be sure it makes sense in three dimensions. Check the heights of shrubs and trees to make sure they fit the space. Be sure each plant is placed where it will receive proper amount of sun or shade.