It's best to seed your lawn in the fall. Lawn seed can certainly be sown at other times during the year; however, fall is the ideal time for seeding. In most areas of the country, a lawn should be reseeded in late August or early September to give the new grass time to grow during the cool fall days.
Step 1 - Rake
You must till the earth with a broom rake. Choose a rake that best suits your needs at the local home improvement store.
A multi-purpose rake may be ideal for removing heavy debris form your lawn. The rake's sharp teeth easily remove the thatch. The flanged teeth facilitate pulverizing the soil.
Step 2 - Till
Once you have thatched and raked the lawn, the thin and bare spots will be more easily visible. Loosen the soil in any of the bare spots to a depth of 1-inch with a speedy cultivator or another tilling tool.
Step 3 - Fertilize
After loosening and pulverizing the soil, use a soil tester to see what nutrients are present in the soil. Buy lawn fertilizer that specifically provides the nutrients least present in the soil, and apply it to the newly prepared area. Use your rake to level the fertilizer on the surface.
Step 4 - Loosen Compacted Dirt
Loosen the soil to a depth of 6-inches if the bare spots have become compacted by foot traffic. Pound the soil and add a small amount of peat moss or gypsum to keep it loose long after you have reseeded the area.
Step 5 - Select Seeds
Reseed with a top-quality seed once the soil is thoroughly loosened and leveled,. Purchase a grass seed mixture that is specially prepared for the type of location you are reseeding.
Some seed mixtures are good for areas which receive little direct sunlight. Other mixtures are designed to reseed sunny areas. The customer service person at you local home improvement store should be able to help you decide which see mixture is best for your lawn.
Step 6 - Planting
Plant 6 seeds per square inch in bare spots by hand. Adding any more or less than the recommended seed density will result in waste. Once the seeds are sown, mist the area with a garden hose.
Step 7 - Protecting
The grass will grow more quickly if you cover the reseeded areas with clear sheets of polyethylene plastic to retain moisture and eliminate the need to constantly sprinkle. Use small rocks, dirt, or stakes to secure the edges of the plastic.
Step 9 - Watering
Remove the polyethylene cover as soon as the seedlings sprout. The cover is only beneficial during the germination process, after which time it will only kill the seedlings. Keep the soil moist by misting it lightly 2 times per day until the grass is 1-inch high. Continue to water newly seeded areas once per week until the new grass is 3-inches tall.
Courtesy of the National Retail Hardware Association.