Many patchy lawns suffer from compacted soil, which deprives grass roots of needed oxygen. Removing plugs of soil with a core aerator ($40 per half day to rent) allows air and water to penetrate the ground and leaves space for surrounding soil to expand and loosen. Plan ahead and reserve the core aerator for at least half a day for an average-size lawn. It’s best to use the aerator when the soil is moist. You’ll need a truck or trailer to haul the core aerator home.

The machine weighs 150 to 200 lbs., so it takes some muscle to move around. If you’re not up to the task, consider hiring a lawn service for this part of the job (it may not cost much more than renting the aerator). Allow a day between aerating and seeding to let the soil plugs dry. Dry plugs will break up easier when you blend them in along with the dressing of topsoil.

Pick a grass seed mix that fits your climate as well as soil and shade conditions. There are many great sources of information.

If you have Internet access, check www.seedsuperstore.com or a similar site. You can also call your local county extension office or ask at the nursery for advice. Make note of your soil type, whether it’s heavy clay or well-drained loam, and how much sunlight the area gets. Pick seed that’s meant to grow best in these conditions and in your climate.

Measure your lawn and calculate the amount of seed you’ll need based on the coverage rates for your seed (listed on the package). For small areas, throw out the seed as if you were feeding birds. For larger areas, use a drop spreader or broadcast spreader. Divide the seed in half and apply it in two passes at right angles to each other. Set the spreader for half the recommended application rate, or to about 20 percent open if there are no settings, and spread the first half of the seed. Keep a close eye as you’re applying it so you don’t run out. It’s better to err on the side of spreading it too thin at first. You can always go over the area again.

The final step in the renovation is to cover the seed with a thin layer of soil. Buy bags of soil from the nursery for small areas. If you’re reseeding an entire lawn, it’ll be more economical to order topsoil delivered. Call a nursery or landscape supply company and say you want screened and pulverized black dirt for top dressing your lawn. You can also use dry, screened soil from your yard. One cubic yard of soil will cost about $30 plus delivery and cover about 1,300 sq. ft. at 1/4 in. deep. Spread the soil and rake it to create a thin, even layer over the seeds.

Lightly water the seeded area two or three times a day for 5 to 20 days until the seed sprouts. As the grass reaches 1 to 2 in. tall, water once a day, but leave the sprinkler on long enough to wet the roots, which are 1 to 2 in. deep. You can mow the grass when it’s about 3 in. tall.

1. Loosen the soil with a rented core aerator. Make four or five passes over the lawn at angles to each other. Let the cores dry a day or so before seeding.

2. Spread the grass seed at about half the rate recommended for new seeding of bare soil. Seed small areas by hand. Use a drop spreader or broadcast spreader to seed large areas.

3. Spread a 1/4-in. layer of topsoil over the seeded area. Fling the soil from the shovel to distribute it evenly.

4. Rake the surface with a fan or leaf rake to break up the soil plugs and spread the topsoil over the seeds. About 10 percent of the seeds will show. Water the new seeds with a sprinkler.

From The Family Handyman - September 2003