Trees and shrubs not only have aesthetic appeal, they also serve useful purposes in a landscape. If planned and planted properly, trees and shrubs help maintain or deflect heat from a home, block strong winter winds and provide insulation. The key is to properly plan, with these goals in mind.
A home gathers much of its heat from sunlight. This heat either comes streaming through the windows or is absorbed through the roof. Because the Chicago area experiences such drastic temperature changes, it’s important to select tree and shrub varieties that will benefit the home in multiple seasons. It’s also important that the trees and shrubs are planted in the proper location in the landscape. A deciduous tree, which loses its leaves in the fall, will successfully block sunlight on hot summer days, but also help heat a home during winter. Sunlight is captured by the home and used as heat on sunny winter days. Plant taller deciduous trees on the south side of a home, where the sun is highest at mid-day and the most intense. Tree varieties that work well for this situation include Oaks, Shagbark Hickory, Kentucky Coffeetree, Honey Locust and Ohio Buckeye. Plant shorter or lower branched deciduous trees on the west side of a home to provide shade from the late afternoon summer sun, but still allow sunlight in the winter. Serviceberry, Crabapples, Japanese Tree Lilac, Cornelian-Cherry Dogwood and hardy Magnolia varieties are lower growing trees that work well on the west side.
Evergreen trees and shrubs also play a part in a landscape that promotes energy efficiency. Cold winter winds are blocked from a home when Evergreen trees are strategically planted on the north side. A well-planned Evergreen windbreak can reduce energy costs by up to 40 percent. Select an Evergreen variety that grows tall and dense, relative to the size of the home. It’s important that the windbreak isn’t massively larger than the home. This isn’t appropriate visually and covers more space than is necessary. Spruce, Fir and some Pine varieties are good choices for large spaces. In smaller areas Yew, Red Cedar and Arborvitae work well. Use taller growing Evergreen shrubs when space is limited. Plant the Evergreens in a staggered pattern, with the taller Evergreens furthest from the home and smaller Evergreen trees and shrubs closer to the home. Use at least two or more Evergreen species in the windbreak to promote diversity in the landscape. The windbreak should be no closer than 50 feet from the home and consist of two to three rows of plantings. The rows should run along the north side of the landscape and form an L-shape, with the bend pointing to the northwest. This blocks the strongest winter winds.
Landscaping around the foundation also affects a homes’ energy efficiency. Shrubs planted near the foundation provide shade, a smaller windbreak and insulation. To maximize the energy a home receives from the sun during the winter, avoid planting Evergreen shrubs that block south-facing windows. Do use Evergreen shrubs on the side of the home that is most windy, to block snow drift and strong winds.
A landscape created with energy efficiency in mind will not only provide utility savings, but is also eco-conscious and beautiful. Following a specific course of action in the beginning of a landscape project will help in reaping the rewards in the future.
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