Picture a healthy green lawn: perfect for lounging...great for ballgames and rolling around with the kids and cookouts...a real asset to your home. But did you know that your lawn—and how you take care of it—can also help the environment? Healthy grass provides a feeding ground for birds, which find it a rich source of insects, worms and other food. Thick grass filters contaminants from rainwater, prevents soil erosion and absorbs many types of airborne pollutants, like dust and soot. Grass is also highly efficient at converting carbon dioxide to oxygen, a process that helps clean the air.

Caring for your lawn properly can enhance its appearance and contribute to its environmental benefits. You don't have to be an expert to grow a healthy lawn. Just keep in mind that the secret is to work with nature. This means creating conditions for grass to thrive and resist damage from weeds, disease and insect pests. It means setting realistic goals for your lawn, whether you or a professional lawn care service will be doing the work. And if you choose to use pesticides, it means using them with care so as to get the most benefit and reduce any risks.

Tending to your lawn in an environmentally sensible way can have a bigger impact than you might think. Your lawn is only a small piece of land, but all the lawns across the country cover a lot of ground. That means you and your lawn care activities, along with everyone else's, can make a difference to the environment, and that's why taking care of the environment begins in our own backyards.

To start, think about lawn care as a preventive healthcare program, like one you would use to keep up your own health. The idea is to prevent problems from occurring so you don't have to treat them. As they say, an ounce of prevention is worth a pound of cure. A healthy lawn can compete with most weeds, survive most insect attacks and fend off most diseases—before these problems ever get the upper hand.

Your lawn care program should be tailored to local conditions—the amount of rainfall you get, for example, and the type of soil you have. No matter where you live, though, a preventive healthcare program for your lawn should have the following steps:

    •    Develop healthy soil.
    •    Choose a grass type that thrives in your climate.
    •    Mow high, often and with sharp blades.
    •    Water deeply, but not too often.
    •    Correct thatch buildup.
    •    Set realistic goals.

1. Develop Healthy Soil

Good soil is the foundation of a healthy lawn. To grow well, your lawn needs soil with good texture, some key nutrients and the right pH, or acidity/alkalinity balance.

Start by checking the texture of your soil to see whether it's heavy with clay, light and sandy, or somewhere in between. Lawns grow best in soil with intermediate or "loamy" soils that have a mix of clay, silt and sand. Whatever soil type you have, you can probably improve it by periodically adding organic matter like compost, manure or grass clippings. Organic matter helps to lighten a predominantly clay soil and helps sandy soil retain water and nutrients.

Also check to see if your soil is packed down from lots of use or heavy clay content. This makes it harder for air and water to penetrate, and for grass roots to grow. To loosen compacted soil, some lawns may need to be aerated several times a year. This process involves pulling out plugs of soil to create air spaces, so water and nutrients can again penetrate to the grass roots.

Most lawns need to be fertilized every year because they need more nitrogen, phosphorus and potassium than soils usually contain. These three elements are the primary ingredients found in most lawn fertilizers. It's important not to over-fertilize—you could do more harm than good—and it's best to use a slow-release fertilizer that feeds the lawn slowly. It's also important to check the soil's pH. Grass is best able to absorb nutrients in a slightly acidic soil, with a pH of 6.5 to 7.0. Acidic soil can be "sweetened" with lime; soil that's not acid enough can be made more sour by adding sulfur.

Have your soil tested periodically to see whether it needs more organic matter or the pH needs adjusting. Your county extension agent (listed in your phone book under county government) or local nursery should be able to tell you how to do this. These experts can also help you choose the right fertilizer, compost and other "soil amendments," and can advise you about aerating if your soil is compacted. If a professional service takes care of your lawn, make sure it takes these same steps to develop good soil. There's no getting around it: Your lawn's health is only as good as the soil it grows in.

2. Choose a Grass Type That Thrives in Your Climate

The right type of grass—one that suits your needs and likes the local weather—will always give better results. Grasses vary in the type of climate they prefer, the amount of water and nutrients they need, their resistance to pests, their tolerance for shade and the degree of wear they can withstand.

If you're putting in a new lawn, do some research to identify the best grass type for your needs. If you're working with an established lawn that fails to thrive despite proper care, you might consider replanting with a different type of grass. Why struggle to grow grass that's susceptible to fungal disease if you live in a humid climate, or attempt to cultivate a water-loving species if you live in an area with water shortages? Grass that is well adapted to your area will grow better and resist local pests and diseases better.

New grass varieties and mixtures come out on the market every year. Ask your county extension agent for recommendations.

3. Mow High, Often and with Sharp Blades

Mowing high—that is, keeping your lawn a bit long—will produce stronger, healthier grass with fewer pest problems.

Longer grass has more leaf surface to take in sunlight. This enables it to grow thicker and develop a deeper root system, which in turn helps it survive drought, tolerate insect damage and fend off diseases. Longer grass also shades the soil surface, keeping it cooler, helping it retain moisture and making it difficult for weeds to germinate and grow.

A lawn's ideal length will vary with the type of grass, but many turf grass species are healthiest when kept between 2.5 and 3.5 inches. You may have to readjust your mower—most are set too low.

It's also important to mow with sharp blades to prevent tearing and injuring the grass. In addition, it's best to mow often, because grass adjusts better to frequent mowing. The rule of thumb is to mow often enough that you never cut more than one-third of the height of the grass blades. Save some time and help your lawn and the environment by leaving short clippings on the grass—where they recycle nitrogen—rather than sending them in bags to the landfill.

You don't have to grow a foot-high meadow to get good results. Just adding an inch will give most lawns a real boost.

4. Water Deeply, but Not Too Often

Watering properly helps your lawn grow deep roots, making it stronger and less vulnerable to drought. Most lawns are watered too often and with too little water. Water only when the lawn really needs it, and then slowly and deeply. This trains the grass roots down, whereas frequent shallow watering trains the roots to stay near the surface, making the lawn less able to find moisture during dry periods.

Every lawn's watering needs are unique, depending on rainfall, the grass and soil type, and the lawn's general health. Even in very dry areas, no established home lawn requires daily watering.

Try watering in a way that imitates a slow, soaking rain by using trickle irrigation, soaker hoses or other water-conserving methods. It's best to water early in the morning to reduce evaporation. Apply about an inch of water—enough that it soaks 6 to 8 inches into the soil. Let it dry thoroughly before watering it again.

The best rule is to water only when the lawn begins to wilt from dryness—when the color dulls and footprints stay compressed for more than a few seconds.

5. Correct Thatch Buildup

All grass forms a layer of dead plant material, called thatch, between the blades and the soil. When thatch gets too thick—deeper than a half inch—it prevents water and nutrients from penetrating to the soil and roots. Some grasses tend to form a thick layer of thatch. Overuse of fertilizer can also create a heavy layer of thatch.

Reduce thatch by raking the lawn or using a machine that slices through the thatch layer to break it up. Sprinkling a thin layer of topsoil or compost over the lawn will also help.

In a healthy lawn, microorganisms and earthworms help keep the thatch layer in balance by decomposing it and releasing nutrients into the soil.

6. Set Realistic Goals

Forget putting-green perfection. Did you know that a lawn with 15 percent weeds looks practically weed-free to an observer? Even a healthy lawn probably has some weeds or insect pests, but it also has beneficial insects and other organisms that help keep pests under control.

Also realize that grass just can't grow well in certain spots. At the base of a tree, for example, you might have better luck with wood chips or shade-loving ornamental plants like ivy, periwinkle or pachysandra. If your climate is very dry, consider converting some of your lawn to dry-garden landscaping.

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