The ongoing energy blackouts in California and the rising cost of our own home heating fuel this past winter give cause for all of us to focus on energy conservation.
Proper landscaping can make a significant difference in the amount of energy needed to keep your home comfortable summer and winter. Use trees, shrubs and vines to reduce heat gains in the summer and heat losses in the winter by modifying the climate around your home. They can provide protection from cold winter winds and can provide shade from our hot summer sun.
Summertime shade can be obtained by strategically placing plants along the sunny sides of your home. Use plants to shade the south-facing roof and walls that are heated by the midday sun. Be sure to also shade east and west facing walls since they receive a considerable amount of direct sun in the morning and afternoon.
The recommended way to provide shade is to plant deciduous trees in an arc so that at maturity they will be properly spaced and provide shade. Location depends on the shape of the tree crown, the position of the sun, the height of your roof or walls, desired window views and overall aesthetic appeal as well as the presence of overhead wires and underground pipes. Obviously, growth of shade trees is a long-term proposition. Consider planting a mix of faster-growing trees with the more desirable slow-growing trees. For the west side of your home, consider evergreens for both wind protection as well as shade.
For a windbreak against cold winter winds, plant upwind from your home. The distance will depend on the tree height. The optimum distance for reducing wind velocity is about one to three times tree height, but even six to 10 times tree height provides reasonable protection. This means a Colorado blue spruce which grows up to 100 feet high can be placed from 100 to 1,000 feet away from your home to provide a reasonable windbreak.
Because wind eddies from around the ends of a windbreak, the plants should extend 100 feet beyond the area to be protected. Any gaps or openings in the windbreak cause a funnel, which accelerates the wind and reduces windbreak effectiveness.