Step 2: Add clover and other grasses.
If you're lucky, you already have some clover in your lawn. If not, it's easy to add it by overseeding, or planting on top of what's already there. In spring or autumn, rough up the surface of the lawn with a metal garden rake. Mix the clover seed with sand or finely screened compost to ensure even distribution. Sow two ounces of clover seed per 1,000 square feet for a moderate clover cover, or up to eight ounces if you want the clover to dominate the turf. After sowing, water your lawn deeply and keep the soil surface moist until the clover germinates. The result will be a soft, cushy, deep-green lawn that stays lush through spring, summer, and fall.
If you can't give up the idea of an all-grass lawn, you can still go organic without clover. Use the same overseeding technique to introduce a low-maintenance turfgrass, such as hard fescue or sheep fescue, to your Northern lawn. In the South, try buffalograss or blue gramagrass. If you're starting over, consider an ecology-lawn mix that incorporates turf-type fescue with flowering plants, such as English daisy and yarrow. More than a lawn but less than a meadow, an ecology-lawn mixture can be mowed and used like turf.
Like fertilizing, watering calls for restraint. Daily shallow watering discourages grass roots from digging deep to find soil moisture, so when drought strikes, a lawn is more susceptible to damage. Deep watering, every two weeks or so, is better. In fact, if you grow the proper turfgrass for your area—if you're not trying to grow bluegrass in Arizona, for example—then you can probably get by without any watering. Yes, the lawn may lose some of its luster during dry months, but it will spring back when rains return.
No water? Little fertilizer? Tall grass? How is this lawn going to look? Better than ever. In time, it will be thicker and sport a more honest green color than it ever would with chemical fertilizers, even as its appearance changes with the seasons—as nature intended.
Step 4: Banish weeds and insects naturally.
Granted, no lawn will ever be 100 percent weed-free, but your mowing, feeding, and watering practices will gradually reduce the weed population. And in the meantime, there are effective, organic weed-control strategies. One of the best is corn gluten meal, which prevents many grassy and broadleaf weeds, including crabgrass, from germinating.
Apply it early in the season, before the soil reaches 55 degrees, at a rate of 20 pounds per 1,000 square feet. Do it again in the late summer and you'll stop weeds from taking hold.
Insects are not a huge problem on a lawn, especially one that's been strengthened by organic care. Still, there are a few bad characters that can do some damage to your turf. Grubs, for example, feed on grass roots, causing large patches of turf to turn brown and die. Fortunately, there's Milky Spore, a bacteria that's poisonous to grubs—and only grubs—and a favorite of organic gardeners for more than 50 years. A little goes a long way: Apply four ounces per 1,000 square feet in the spring or summer, and, in most climates, it will colonize the soil to offer long-term coverage.
Step 5: Enhance your soil.
In the end, organic gardening always comes down to the soil. When you're dealing with lawns, it's hard to improve the soil in traditional ways; you don't want to dig up the turf to add nutrients and microorganisms. But you can topdress: Simply use a spreader to apply a quarter-inch-deep layer (or less) of finely screened compost to the turf. The compost will invigorate the soil and stir up a slew of microorganisms as it sifts below the surface, improving drainage and reducing compaction along the way.