Regional Gardening Reports :: National Gardening Association

In the Garden:
Southwestern Deserts
July, 2003
Regional Report

Share |

Deciduous grapevines grow over a patio ramada at Pima County (AZ) Cooperative Extension, providing filtered light in summer.

Planting for Energy Savings

Today's thermometer topped 115 degrees, and my air conditioner was cranking on overtime. It's too hot for any sane person to be outdoors planting, but a convenient time to contemplate whether your landscape promotes energy efficiency and relief from the relentless heat. Up to two-thirds of home energy costs go for heating and cooling. Experts say that well-placed trees and shrubs can reduce that amount up to 60 percent.

A good place to start is with the placement of trees. A strategically located tree can cool your house in summer, warm it in winter, and reduce reflected heat and glare.

Determine Exposure
Start by figuring out where the sun is in relation to your home. What are the north, south, east and west exposures? The southern and western exposures are the hottest, with the most direct sunlight. The northern exposure is the coolest and shadiest. If you must create your landscape in increments, start by shading the southern side, which is exposed to the sun for the longest period in summer.

Block the Sun
About 40 to 45 percent of the heat coming into homes comes in through the glass, so your first goal is to have well-placed plants blocking it. Select deciduous trees (those that drop their leaves in the fall) with a wide branching pattern. Their spreading foliage provides needed shade in summer; when temperatures cool in winter, their bare branches allow the sun to shine through the windows to warm your home.

Beyond Trees
Vines can also reduce the sun's intensity around your home. Over the years I've planted a variety of vines on the cement block wall surrounding my home. They reduce the reflected heat and glare that strikes the patio area; and, psychologically, their green foliage provides a cooling respite. Vines also can be trained up trellises and arbors, but make sure the supports are sturdy. My pink trumpet vine and I enjoy a yearly contest: I try a new trellis and the vine tries to tip it over.

We tend to think of big leafy trees as primary shade providers, but cacti and succulents also can provide relief. They cast shadows late in the day when the sun is low, and are well-adapted plants for summer's intense sun and heat. Take some time to sketch where the sun's angles are hitting your house this summer so you will be ready to add some strategically placed plants when fall rolls around.

Care to share your gardening thoughts, insights, triumphs, or disappointments with your fellow gardening enthusiasts? Join the lively discussions on our FaceBook page and receive free daily tips!


Today's site banner is by nmumpton and is called "Gymnocalycium andreae"