The Use of Shrubs in Energy Conservation Plantings

Abstract

Although most energy conservation landscape analyses emphasize the use of trees, this study has analyzed the use of shrubs to reduce cooling requirements of buildings in warm-humid climates. Reductions in temperatures of walls of concrete-block houses as a result of shrubs being planted immediately adjacent to the walls have been determined for warm summer days. During periods of direct sunlight, temperatures of walls shaded by shrubs were 24 to 29°F cooler than uncovered walls. Shrub-shaded walls were significantly cooler even during periods of no direct solar radiation. Shrubs located immediately adjacent to walls were also effective in reducing prevailing summer winds impacting on a building by 75 to 93%. These experimental results have been used to develop some specific landscape design strategies which use shrubs to reduce residential air conditioning.