There are lots of electricity-free home-cooling tricks, including reflective roof paint for your house and ice-cold gel packs for your neck. Add to that a selection of outdoor sources of shade, and you may just be able to avoid turning on your air conditioner (or at least, turn it on less often).
Any bit of shade you can cast on your south- or west-facing walls will help reduce your home's heat gain and thus lower your utility bills. Planting shade trees in strategic locations is a good long-term plan, but even the fastest-growing kinds, such as hybrid poplars, will take years to grow tall and wide enough to provide meaningful shade. Interior or exterior shades or awnings are another option, but they can cost real money.
The answer? Fast-growing "living shades" that you can plant this weekend, which will be cutting your energy bills as early as mid-July. Free-standing plants, placed in a garden bed or in large containers lined up along the south or west walls of your house, are quick-growing and inexpensive sources of shade, or you can opt to start shade vines that will crawl up the side of your house or porch. Even a row of hanging baskets with trailing plants in them, an upside-down tomato planter or two, for instance, or window boxes with hanging plants, can cast a meaningful patch of shade on the wall below the window. Every little bit will help, so do what you can and enjoy the home-cooling goodness of green plants!
Shady Free-Standing Plants
Plant or place pots containing the following varieties a few feet away from your walls to allow for air circulation. If planting in your garden, seed a double row if you have room, staggering the plants in a zigzag pattern for optimal shade.
• Sunflowers (Helianthus sp.): Tall, single-head seed varieties like ‘Mammoth’ and ‘Sunzilla’ can reach 16 feet in optimal conditions. Birds love the mature heads in fall and winter.
• Corn (Zea mays): Dry types of corns, such as ‘Hickory King’ or ‘Bloody Butcher’, tend to be taller than sweet corn and can reach 12 feet tall. Some types have reddish foliage. Harvest the ears for grinding or let your local wildlife enjoy it.
• Broom corn (Sorghum vulgare): This is actually a type of sorghum, with stiff seed heads used to make brooms. A large annual grass that grows 6 to 15 feet tall, broom corn is available with a range of red, brown, and yellow seed heads. Birds love the seeds.
• Cannas (Canna sp.): Although actually a perennial, in temperate climates cannas can be grown as an annual from roots. Tall varieties can reach 6 to 10 feet tall. The tropical foliage can be green, reddish, or variegated, and the showy flowers can be yellow, pink, red, or variegated.
Fast perennial options (they grow tall each summer, die and/or get trimmed to the ground each winter): Jerusalem artichokes (Helianthus tuberosus), tall ornamental grasses, and tall perennial flowers such as joe-pye weed (Eupatorium purpureum) and golden glow rudbeckia (Rudbeckia laciniata hortensia).
Shade That Grows Up Your Walls
Vines will grow very quickly and don't require much on your part to maintain them. Some can even produce edibles!
• Runner beans (Phaseolus coccineus): Tasty snap beans or dry beans follow red, white, salmon, or bicolored flowers. They grow to be about 15 feet tall.
• Hyacinth bean (Lablab purpureus): Primarily an ornamental, the very small pods of the hyacinth bean can be cooked and eaten. The plant has green or reddish foliage with showy white or purple flowers and grows to 20 feet or more.
• Morning glory (Ipomoea purpurea) In agriculture, this plant is actually considered a weed, but its heart-shaped leaves and showy white, pink, red, blue, purple, or bicolored flowers make it a nice addition to home gardens. The vines grow to 10 feet.
• Cardinal climber (Ipomoea x multifida): Good for a dry, hot climate, the red flowers and fernlike foliage of this vine attract hummingbirds, in addition to shading your house. It grows to 20 feet.
• Gourds (Cucurbita pepo and others): Fast-growing vines with small flowers that grow into colorful gourds for fall decorations or crafts, gourd vines need to be planted next to a sturdy trellis. If you don't have a sturdy trellis, stick with varieties that make 3 to 4 inch gourds. Loofah gourds produce sturdy sponges—the loofah sponges you often see in stores—given a long season, and are fun to grow if you have a strong trellis for them.
• Hops (Humulus lupulus): The plant that lends beer its taste, hops can grow a foot or more a week to reach at least 40 feet tall. Most varieties are green-leaved, while 'Aureus' has bright yellow-green leaves. In late summer, cones appear, adding visual interest.
Exotic vine crops such as bitter melon (Momordica charantia) and Armenian cucumber (actually a melon, Cucumis Melo) can also be interesting additions.
If you choose a vine, you'll need to give it extra "support," either through a sturdy trellis, as mentioned, or some other part of your house or porch that will be able to support the growing load and not be damaged by it. To attach the plant to its support, use lengths of sturdy twine or a biodegradable netting trellis tied to your home's eaves or porch. You can also plant your vines so they grow up a bamboo cane or long stick. If you go this route, be sure to attach it to your home so it doesn't tip over or collapse during a strong storm. Lacking a trellis or other structural support, stretch your trellis netting or twine between two firmly installed fence posts set a few feet away from the wall to be shaded.
Caring for your hard-working shade makers:
For best growth and optimum performance apply a generous layer of compost at planting time, add a generous layer of organic mulch (such as straw or dry grass clippings) to conserve water and reduce weed problems, and water as needed to keep the soil moist, but not soggy, all season long. If you want to be able to see out your windows, use a sharp pair of scissors to remove a few leaves on a level with the window, leaving the stems intact.
Farm gal, library worker, and all-around money-pincher Jean Nick shares advice for green thrifty living every Thursday on Rodale.com.
For more home cooling tips, see: