How to Prepare the Ground for New Grass Seed

Follow the directions on the pH test kit and perform a test on the soil in which you are planning to plant the grass seed. Take tests at few different locations in the area. A pH of between 6.0 and 7.0 is desirable.

Add hydrated lime to the soil if you need to raise the pH of a soil that is too acidic. Application rates will vary according to soil type. The following recommended application rates are designed to raise soil pH by one point. Add 4 oz. of hydrated lime per square yard in sandy soil, 8 oz. per square yard in loam soil, 12 oz. per square yard in clay soils, and 25 oz. per square yard in peat soils.

Add ground sulfur (also known as farm sulfur, dusting sulfur, or rock sulfur) to the soil if you need to reduce its pH by one point. Use 1.2 oz. of ground sulfur per square yard for sandy soil, 3.6 oz. per square yard for all other soil types.

Work the additives into the soil completely by tilling the soil to a depth of 4 to 6 inches. Rake the surface and remove any debris, rocks, and weeds that have come to the surface as a result.

Add some sphagnum peat and/or topsoil to the area that will be seeded. A soil that is in average condition may require only 1 inch of sphagnum peat, while you may add up to 6 inches of a topsoil and sphagnum peat mixture to fortify soil that is in poor condition. Till the soil again, mixing these additives into the soil thoroughly.

Rake and level the soil, and then apply a lawn starter fertilizer to the soil. Take care to apply the starter fertilizer at the proper rate to avoid adding to much nitrogen to the root zone. To be safe, apply no more than 1 pound of nitrogen per 1000 square feet. Fertilizers are labeled with three numbers that denote their nitrogen, phosphorus, and potassium (N-P-K) content. The following are some typical N-P-K contents for lawn starter fertilizers and their associated recommended application rate.
For a 5-10-5 fertilizer, apply at a rate of 20 lb. per 1000 square feet.
For a 16-20-0 fertilizer, apply at a rate of 6 lb. per 1000 square feet.
For a 10-20-10 fertilizer, apply at a rate of 10 lb. per 1000 square feet.
For a 5-20-10 fertilizer, apply at a rate of 20 lb. per 1000 square feet.

Water down the area so that it is damp, but not soggy. This will cause the soil and nutrients to settle a little, and it is now ready for you to plant the grass seed.