Lawn Care Basics: The Grass is Always Greener
Repairing by overseeding (Step 3)
To compensate for uneven germination in the existing grass, sow seed at the same rate as recommended for new lawns. Most people put the seed on with a common drop spreader. Put half the seed on in strips across the lawn and then apply the other half from a different angle. The exact angle doesn't matter. Just be sure to go over the area thoroughly on two passes to ensure consistent coverage, which makes for a thicker, greener lawn. You can also use something as simple as your fingers or as complicated as a slit seeder to get seed on the soil. Slit seeders are power tools that open up slices of lawn for better seed-to-dirt contact. Find them at your local rental store. Go over the whole area with a weighted garden roller, or top-dress with a good topsoil or fine compost. Water the seed in well. Mow the new grass when it is 3 inches tall at a medium-low setting so the late-sprouting seeds will get good light. Frequent, regular watering--about an inch per week--is essential to establishing a new stand of grass. You can treat it as an established lawn in four to six weeks.