How to Plant Grass in Clay

Apply a layer of organic material such as compost to the top of the soil. According to the National Gardening Association, compost improves the texture and drainage of clay soils. It also adds nutrients to the soil that release slowly as plants need them. The National Gardening Association suggests applying at least 6 inches of compost to a new lawn area.

Till the compost into the soil to a depth of at least 6 inches. Better Homes and Gardens explains that tilling helps break up hard soil and provide aeration for new grass roots

Test the soil pH using an at-home soil testing kit, which most gardening stores sell. Alternatively, send a soil sample to a nursery or local university for testing. The National Gardening Association recommends planting grass in soil with a pH of 6.0 to 7.0.

Add lime to raise the soil pH or sulfur to lower the soil pH until it reaches the ideal range on the testing kit.

Rake the soil to create a smooth lawn surface and provide tiny ridges for the grass seeds to nestle into.

Sprinkle the grass seed onto the soil surface.

Keep the soil moist consistently until the grass establishes itself. Do not overwater, however, since clay soil tends to hold in moisture and prevent root aeration.