Lawns need to be over-seeded about every 3-4 years since grass production begins to slow down after about 5 years causing the lawn to become thin. Its very important you choose a seed that only contains NTEP top rated variety of seed. This ensures the seed is superior in green color, disease and insect resistant, and drought tolerant.
It’s recommended you use a seed slither which places small cuts in the soil and distributes the seed at the same time. This is the best method to cover a large lawn as good seed to soil contact is crucial. You could also use a drop or rotary spreader to do the job. If the seed doesn’t have a good contact with the soil you will need to repeat the overseeding. Its best to rent or to borrow a sliter as its an expense which you will only use the equipment once every 4 years or so. Spread the seed by hand in the small and hard to reach areas. Use a spreader for the open and lager areas. A good rule of thumb is to apply about 16 seeds per square inch. If you apply to many seeds it will cause the seedlings too fight for room and nutrients which will make the grass weak or thin in those areas.
You will need to cover any seeded areas with a mulch and a starter fertilizer. This aids in keeping the grass seeds moist and also encourages germination. Its advised you do not use straw to cover the areas of your lawn as straw has a tendency to contain weed seeds along with the grass seed. Its important to do yearly fertilizing to maintain your lawn care.
Before you apply the new seed, mow the lawn very short. Be sure to loosen the top 1/4 ” soil in the bare areas. Remove all the debris and the dead grass from the area you’ll be over-seeding. Fertilize the bare spots after overseeding.