If your grass is brown, bare, or patchy (or all three!), you’ll first need to do some detective work: Drought, disease, poor soil, compaction, and excessive fertilizer use can diminish your lawn’s health. Your local university extension service can help with soil analysis, or experiment with these chemical-free fixes:
1. Water less often.
When you do, make sure you do it long enough to penetrate 6 inches into the soil. This will create deeper roots, which will make the lawn more resistant to disease and pests, advises Nichelle Harriott, science and regulatory director for Beyond Pesticides, a national advocacy and grassroots nonprofit, in Washington, D.C., who notes that frequent watering can actually promote more weeds.
2. Let your grass grow tall.
You’ll be able to go longer between waterings—at least a week, or longer if it rains. Set mower blades to 2 or 3 inches minimum; this allows grass to develop deeper, drought-resistant roots.
3. Stop beetles from settling in.
Tall grass also discourages beetles from laying their eggs there; when eggs hatch into grubs, they can cause those big brown spots. Ask your local garden center for a chemical-free treatment option that can include nematodes, which are microscopic wormlike organisms that will prey on the grubs and other larvae in your soil.
4. Leave grass clippings on the lawn.
They’ll return important nutrients such as nitrogen and potassium to your soil.
5. “Overseed” to fill in existing bare spots.
Do this by adding extra grass seed all over your lawn in the late summer or early fall. This will fill in patches and crowd out weeds while also giving you a thicker, healthier lawn. “Use a mixture of grass cultivars, and avoid seeds that come pre-coated with pesticides,” suggests Harriott (your local garden center can help you ID a good choice for your location).
6. Aerate your soil.
If you can’t stick a screwdriver easily into your turf, it’s worth renting an aerator, a machine designed to create holes in the soil, to bring back oxygen, encourage microbial communities, and break up compaction so grass can grow.