Brown spots on your lawn are unattractive, not to mention a sign of some type of problem. Before you can correct the brown patches and restore your grass to a luscious green, you must identify the problem. Brown spots can occur as a result of dog urine, over fertilizing your lawn or brown patch disease. Brown spots can also mean that you have white grubs living under your grass.
Water the brown spots often with your garden hose if they are a result of too much fertilizer or dog urine. Both of these add too much nitrogen to the soil, which is why the grass dies out. Water will dilute the nitrogen.
Kill the fungus in your lawn that is causing the brown patch disease, if that is the cause of your brown spots. American Lawns recommends using a fungicide with either benomyl or chlorothalonil as its active ingredient. Follow all of the directions on the product label to completely get rid of the brown patch disease.
Add nematodes to your lawn if you have brown spots because of white grubs. White grubs are the larvae of the Japanese beetle. They feast on the roots of the grass, causing patches of dead grass. Nematodes are safe and will kill the grubs for you naturally. Just mix them with water as instructed on the packaging label, and spray them over your brown spots.
Reseed the brown spots once you have eliminated the cause of the brown spots. The soil will now be ready to grow new, healthy grass.