How to repair bare patches and overseed?

For bare areas larger than a few square feet that need immediate results, purchase sod that matches your grass type. Prepare the soil by loosening the top 2-3 inches, lay the sod tightly with staggered joints (like brickwork), and water heavily for the first 2 weeks.

When applying pre-emergent herbicide in spring, physically skip over or flag any areas where you plan to seed bare patches. Apply pre-emergent only to the established portions of the lawn.

For spring patches that need to fill in fast, choose perennial ryegrass seed. It germinates in 5-7 days — the fastest of any common cool-season grass — giving it the best chance of establishing before summer.

When seeding bare patches, apply a starter fertilizer with elevated phosphorus (e.g., 10-18-10 or 18-24-12) at the time of seeding according to the bag rate.

After spreading seed on a bare patch, cover it with an eighth to quarter-inch layer of finely screened compost. Do not bury the seed deeply — it needs some light to germinate.

Water newly seeded areas lightly 2-3 times per day for the first 2-3 weeks. The goal is to keep the top half-inch of soil consistently moist but not waterlogged. Once seedlings reach 2 inches, transition to deeper, less frequent watering.

Identify your current grass species and buy seed that matches. If you have tall fescue, buy tall fescue seed. If you have Kentucky bluegrass, buy KBG seed or a KBG-dominant blend.

Before dropping any seed, use a garden rake or hand cultivator to scratch the soil surface to a depth of 1-2 inches. Remove dead grass, roots, and debris so the seed makes direct contact with mineral soil.

Loosening the soil gives seeds direct contact with dirt, and the compost layer holds moisture around the seed. Small patches (under 3 sq ft) can establish in spring because they do not require skipping pre-emergent on the entire lawn.

If your lawn has widespread thin areas, plan a full overseeding for late August to mid-September rather than spring. Reserve spring seeding only for small bare patches that cannot wait.