Division of Energy
Residential Energy Efficiency - Landscaping for Energy Efficiency
Planting trees and shrubs around your home will help reduce your heating and cooling costs. How much it reduces costs depends on the choice of plants, where you locate them, the location of your home and its construction.
Trees and shrubs also reduce noise and air pollution and make your home more attractive and more valuable. Therefore, money spent on landscaping your home is a good investment.
An unprotected home loses much more heat on a cold, windy day than on an equally cold, still day. Well-located trees and shrubs can intercept the wind and cut your heat loss. Studies of wind breaks show they can reduce winter fuel consumption by 10 percent or more. Trees and shrubs planted close to a building reduce wind currents that otherwise would chill the outside surfaces. Foundation plantings create a "dead air" space which slows the escape of heat from a building.
Foundation plantings also help reduce air-infiltration losses around the foundation of the house. Closely planted evergreens are suggested for this area.
Deciduous trees lose their leaves in the fall and allow the winter sun to enter the windows and warm the inside space. In the summer, their leaf cover provides cool shade which reduces your home's need for mechanical air conditioning.
The maximum air-conditioning need in Missouri is usually in late July and early August, and most electrical power for air conditioning will be used in the late after noon hours. With this in mind, landscape plantings should include trees and tall shrubs to shade west-facing walls, windows, and the southwest corner of the home during the hottest summer afternoons. Quick-growing vines may be planted on trellises to provide summer shade screens while trees are growing. If there is no roof overhang to significantly reduce the effects of the sun on south walls, deciduous trees and shrubs should also be planted to shade south walls and windows.
When planting trees, choose the site carefully. Plant tall growing trees such as hickory, walnut, oak, pecan, sweetgum and pine well away from any power lines so branches do not tangle in the wires. Avoid planting trees over underground utility lines.
Within the Xeriscape landscape, plants are zoned or grouped according to their water needs. Proper plant location is as important as plant selection. Turf is considered a plant, not a filler. Typically, there are three water use zones; low, moderate and high. This, along with mulch and plant selection, avoids the need for excessive water use.