Air conditioning for cooling homes consumes 5% of the electricity generated in the U.S. With energy costs on the upswing, many homeowners are looking for options to reduce their cooling bills. Although your first thought on this matter may be buying a more energy-efficient air conditioner, you might want to consider using trees and other landscaped plants to shade your home to help reduce cooling costs.

The heat from the sun which windows and roofs soak up can boost your air conditioner use. Putting shading ideas into your landscape plans can help lessen solar heat gain, thus reducing your cooling costs. Shading and evapotranspiration (which is what the process by which a plant moves and releases water vapor is called) from trees can reduce temperatures of surrounding air by up to 9° F (5°C). In fact, air temperatures immediately under trees can be as much as 25°F (14°C) cooler than air temperatures above nearby blacktop surfaces, due to the fact that cool air settles near the ground.

Trees can be chosen with appropriate sizes, densities, and shapes for almost any shading application. You first need to know size, shape, and location of the moving shadow that your shading plant will cast. For blocking heat in the summer but letting it in during winter, select deciduous trees. To provide uninterrupted shade year round, use thick evergreen trees or shrubs.

To provide maximum summertime roof shading, plant Deciduous trees with high, spreading leaves and branches to the south of your house. Trees with branches lower to the ground are better suited to the west, since shade there is required from lower afternoon sunlight. A 6-foot to 8-foot deciduous tree planted close to your home will start to shade windows it's first year. In 5-10 years the tree will shade the roof, depending on the species and the climate. If you have an air conditioner, shading the unit can raise its efficiency by up to 10%.