Planting Shade Trees
The recommended way to provide shade is to plant deciduous trees in an arc encompassing the home on the east, southeast, south, southwest and west sides. Plant shade trees based on their mature height so they will be properly spaced and provide desired shade. Location also depends on the shape of the tree crown, the position of the sun, the height of the roof or walls, desirable views from windows, aesthetic appeal of the overall landscape, and presence overhead wires and underground pipes. A small caliper tree will grow faster into a large tree than a larger caliper tree. If the mature height and shape is not planned for in advance, the location of the tree may cause problems in the future.
Summer shade for a south-facing roof generally depends on having overhanging tree crowns. Trees that do not overhang the roof will not cast much shade on it at midday due to the high position of the sun in the sky. Thus, plant shade trees as close to the home as practical. Choose a species that is not susceptible to breakage. Leaves in gutters are an undesirable consequence of large deciduous trees near the home, but most people can cope with this nuisance. Promptly remove diseased, damaged trees or limbs to avoid damage to the home.
Summer vs. Winter Tree Arrangements
Tree arrangements that provide shade in summer may be detrimental in the winter if they block solar heating. Leafless deciduous trees may reduce the amount of sunlight reaching the home by more than one-third. However, the winter sun is typically less than 45 degrees above the horizon, so shading will be largely from tree trunks. For this reason, plant only those trees needed for summer shade along the southern edge of the home. Prune the lower trunk to allow maximum solar heating of walls and roof in winter. As few as two or three large deciduous trees with well-developed crowns may suffice.
Other Shade Tree Considerations
If a home has a solar device that requires sun during the summer and winter (or if you may want one in the future), plant so no shade is cast on the collectors between 9 a.m. and 3 p.m. at any time of the year. Leave a gap in the tree canopy to allow the sun to shine on collectors during those hours.
Growth of a shade tree is a long-term undertaking. To provide shade faster, mix fast-growing trees among slower growing, more desirable trees. As the slower-growing trees mature, remove the fast-growing trees.
Cover walls that face east or west with clumps of vegetation or attached structures to provide shade to those walls. Use deciduous or evergreen shrubs or small trees that grow high enough to shade the wall. You may prefer evergreens on the west side to provide both summer shade and winter wind protection.
Vines may be grown directly on masonry walls, but on wooden walls grow them on a trellis. Shade east or west walls with a slatted, wooden overhead structure attached to the home. It can be made from 1 inch by 2 inch strips of treated pine, redwood or cedar spaced 1 inch apart and attached to the frame-work. Training vines to grow over the structure will create an arbor.Last updated: October 20, 2017 at 13:01 pm