Water-wise gardening

Valerie Sudol By Valerie Sudol The Star-Ledger
on April 23, 2008 at 2:56 PM, updated April 23, 2008 at 6:40 PM
Drip systems deliver water to the root zone without wetting foliage.

Climate change is bringing hotter summer temperatures to the Northeast and heat spells absent regular rain are the bane of any gardener's carefully laid plans.

It shouldn't take a drought to remind us that water is a limited resource and wasting it is just plain selfish. If we all adopt conservative water-use practices, the world will be a greener place, literally and environmentally.

Learn to water properly. Deep and infrequent watering penetrates the soil and encourages deep roots, a plant's best dry-weather asset. Plants generally will do fine with a thorough soaking twice a week.

Be sure the water you apply penetrates to the root zone -- in sandy soil, 1 inch of applied water may dampen soil to a depth of 12 inches, but in heavy, clay soils, the same output may only reach the top 3 inches. Know your soil.

Get in the habit of digging 6 inches or 8 inches down after watering or after rainfall to learn how water penetrates the earth in your garden. Set out a rain gauge to help you figure out the math of watering.

The best time to water is in early morning, when evaporation is at a minimum. Can't get up before the birds sing, you say? Attach your watering system to a timer and you can awaken at a human hour with your garden already glowing from its pre-dawn drink.

Bear in mind that spritzing plants daily with a garden hose or an overhead sprinkler is the least effective method of watering. Foliage may prevent water from reaching the root zone, and light watering brings roots to the soil surface. At the other extreme, overwatering deprives plant roots of air and can contribute to root rot.

Oscillating sprinklers that send a spray of water overhead are notoriously inefficient. As much as 50 percent of their water output can be lost to evaporation -- more in the heat of midday -- and wind can blow moisture out of the reach of thirsty plants. Sprinklers also waste water by indiscriminately sprinkling paths and lawn areas adjacent to your garden.

The best water equipment by far consists of low-volume soaker hoses and drip systems. These use a fraction of the water required by overhead sprinklers and deliver water to the root zone without wetting foliage, which can promote fungi and mold diseases.

Inexpensive and easy to install yourself, these systems can be covered with a layer of mulch to retard evaporation and conceal the plumbing from view. Once set up, a drip or soaker system affords you the convenience of watering the whole garden with the twist of one tap -- and if you include a timer, you may not even have to exert that much effort.

Keep water where it belongs by creating troughs around vegetables, flowers, shrubs and trees to prevent runoff. Watering slowly also helps the water penetrate dry soil; a strong stream will ricochet off hard, dry soil surfaces and might contribute to erosion.

Mulch around plants to retain moisture and keep weeds at bay. Consider using water from sources that don't deplete the general supply. You can recycle some household water and use submersible pumps to tap water from ponds, natural or manmade, that may be on your property. The old-fashioned rain barrel is poised to make a big comeback -- it just might be the hottest thing in garden equipment this summer.

If you water by hand, choose a high-output watering wand that allows you to apply a concentrated spray directly to the base of the plant. It will extend your reach to hanging baskets and spare your back, too. Many wands have adjustable heads that allow you to choose a fast stream or a gentle shower, depending on what plants require.

The water-wise gardener can keep plants going without putting a strain on water supplies. It's all part of thoughtful stewardship in the garden and beyond the garden gate.