Safe Cures for Lawn Troubles

Walt Whitman called weeds "plants whose virtues have yet to be discovered." Lawn owners would surely agree with him. Unfortunately, they often resort to the nearest weapon -- chemicals -- when common sense, elbow grease, and ingenuity could do the trick.

The nonprofit organization American PIE (Public Information on the Environment) notes that callers to its helpline frequently want opposing things -- the perfect lawn and no chemicals. A call from a Chicago man was typical. He'd brought home several bags of commercial fertilizer and while loading it into his garage noticed the dire warning labels. He thought, "I have a child toddling on this grass. Is this a good idea?"

Those warning labels are there for a reason. Many commercial fertilizers and herbicides may be harmful, and federal regulators continually upgrade controls and warnings.

The key to a chemical-free lawn is patience. Soil that's been chemically treated has lost its naturally occurring, beneficial micro-organisms that nourish healthy plants. Like any addict, it will suffer withdrawal symptoms -- in the case of a lawn, slow or patchy growth.

If you don't want to use chemicals on your lawn, the best defense is a good offense. A healthy, thick lawn created in good soil and topped with a thin layer of compost, manure, or other organic material forestalls the common weeds, bugs, and diseases. When problems do arise in the lawn, natural remedies exist. There are alternatives to using herbicides, pesticides, and fertilizers on the country's nearly 30 million acres of lawn. Along the way to becoming chemical-free, you may even find a virtue or two in some common weeds.

Crabgrass

Crabgrass, the weed everyone loves to hate, tops America's list of lawn complaints. The best crabgrass preventer is a healthy, thick lawn and soil with the proper pH balance (7.0-7.5). Perennial rye grass is the best competition for crabgrass. It also provides some insect control, as it emits a natural poison that gives some small, damaging bugs the "flu."

Fertilizing is key and must be done in the spring and in the fall. Crabgrass thrives in compacted lawns. Aeration can help (see page 118). A mixture of 1 pint of hydrogen peroxide, diluted to 3 percent, per 100 square feet of lawn can help eradicate the pesky plant.

Corn gluten meal, a relatively new and increasingly popular natural herbicide, appears to be successful at preventing crabgrass and other common weeds. A by-product of milling corn, it is completely benign. A three-year systematic application can yield a nearly weed-free lawn. Research at the University of Iowa-Ames showed that 60 percent of weeds are eliminated the first year, 80 percent the second, and 90 to 100 percent the third year of corn gluten meal application. Some companies sell a pelletized form containing potash and nitrogen, but you may have to search a bit or ask your retailers to stock it. (Gardens Alive! sells W.O.W. [Without Weeds] in a 50-pound bag, enough to treat a 2,500-square-foot lawn the first year. Call 812-537-8650 for details.)

Dandelions

Your neighbors probably wouldn't stand for a dandelion yard, but consider this: Dandelions make great wine, are a natural diuretic, can be dried and made into coffee, and can be braided into lovely necklaces. You can eat their young leaves in salads, and in fact, they were brought to this land as an exotic green. They're an excellent source of potassium, phosphorus, calcium, and vitamin A.

Not convinced and still want to get rid of your dandelions? Get a weeding fork. Dandelions have a two-year life cycle. When they're in the first year and appear as basal foliage, dig them out with a vengeance. It's great exercise. If you miss some and they flower the next year, dig them out before they reach the seed (white puffy) stage. If you let them go to seed and spread their progeny, you'll have to start the process all over again.

A thick, healthy lawn is again the best defense against dandelions, as it is for other common broadleaf weeds such as creeping charlie (jenny) and quack grass.

Grubs/Japanese Beetles

Insecticides or pesticides are hardly ever necessary to control the most common lawn pests. Japanese beetle grubs and their adult counterparts are a problem in much of the eastern United States. They cause lawns to turn yellow and die but are fairly easily controlled through nonpoisonous means. In the grub stage of late spring and fall (beetles have two life cycles per season), spray the lawn with 2 tablespoons of liquid dishwashing soap diluted in 1 gallon of water per 1,000 square feet. The grubs will surface and the birds will love you. Spray once each week until no more grubs surface. In the adult beetle stage, handpick them and squish them, or drop them into a bucket of soapy water.

Two biological controls for Japanese beetles are beneficial nematodes and milky spore disease. These will not harm people or pets. Milky spore disease is a bacterium that controls chewing insects, including beetles, and can be purchased under several brand names. Once established in your soil, it lasts up to 20 years as an effective beetle control. Buy it at your local garden center, follow the directions to the letter, and apply in late spring or fall.

Chinch Bugs

Chinch bugs are annoying creatures that smell bad when you crush them and make yellow or brown patches in your lawn, especially in dry conditions. Watering well for three to four weeks can keep them under control. Or soak the sod with a solution of 1 ounce of dish soap and 2 gallons of water, and cover the grass with a flannel sheet to catch the bugs as they flee. Experts agree that insecticides and human control have nearly the same efficacy against chinch bugs.

Thatch

A spongy lawn indicates a thatch problem. This tightly intermingled layer of dead and decaying vegetation -- an unhealthy build-up of organic matter that can cause brown patches in a lawn -- indicates a pH imbalance. Thatch is particularly a problem in lawns previously treated with chemicals where the grass's natural ability to decay has been destroyed. Dry thatch repels water, while wet thatch invites fungal diseases.

The best control is raising the lawn soil's pH level. One way to do this is to rent a power rake (inquire at your garden supply center), which uses rigid wire tines or steel blades that slice through the thatch and lift the debris and some soil to the surface to encourage natural decay. The best time to dethatch is in late spring. Don't do it during midsummer, when the lawn may be stressed, or when the lawn is wet. Hand raking is less harsh but can be impractical and back-breaking work for large lawns. Molasses diluted with hot water and sprayed on the lawn can help stimulate natural organisms to eat the thatch layer.

Aeration also helps. Healthy soil should be 50 percent solid, 25 percent water, and 25 percent air. To achieve this ideal, improve overall lawn health, and help prevent fungal diseases, you can rent "plug" machines that take out chunks of soil and redeposit them on your lawn. Some catalogs sell aerating sandals with long spiked soles. Gardeners are meant to strap these scary-looking things to their feet and walk around on the lawn. Users claim, however, that they take far too much weight and leg strength to be effective.

You can manually aerate your lawn with a spading fork; experts recommend about one hole per every few inches of lawn. Get to work in the spring or whenever compacting and thatch seem to be a problem.

To obtain a free brochure on natural lawn care, contact American PIE, 124 High St., Box 340, Glastonbury, CT 06073-0340; 800-320-APIE (2743); www.americanpie.org.

Four Steps to a Healthier Lawn

• Test your soil: The pH balance should be 7.0 or more -- 6.2 to 6.7 puts your lawn at risk of fungal diseases. If the pH is too low, correct it with liming, best done in the fall.
• Mow only when the grass is at least three inches tall. This encourages deep roots. Leave grass clippings on the lawn as a natural fertilizer.
• Don't over-water. Make the lawn seek its own source of water, building longer, sturdier roots. Cut back on water especially in midsummer to let the lawn go dormant, strengthening it for fall and winter.
• Control the weeds by promoting healthy lawn growth with natural fertilizers in spring and early fall.