Clay soils are the results of rocks being weathered over a period of time. Red clay soil is the most common of all clay soils. When the soil has too much clay it can be difficult for plants to penetrate for growth. The soil becomes very hard and compacted after it dries, which makes it hard for plants to get oxygen to the roots. Clay can also cause drainage problems by allowing water to puddle and stand for too long. There are several ways to improve clay soil in your lawn.
Apply 2 to 3 inches of organic compost to the soil and use a rototiller to mix the compound into the soil. Wait until the soil is completely dry before you use the rototiller so you will not further compact the soil. Alternately, add 6 inches of high-quality topsoil on top of the clay before you plant anything. This may not be the most cost effective method if you have a large area to treat.
Pass a lawn aerator over your lawn so the organic compost can penetrate the soil. Pass the aerator over the grass several times and in several different directions. It will not harm your existing lawn.
Remove the plugs of soil that the aerator pulls out. Dispose of them in another location or throw them away in lawn bags. This will prevent the clay from compacting back down into the lawn.
Spread a layer or organic compost over the aerated lawn. Fill a wheelbarrow full of the compost and use a shovel to spread the matter over the existing lawn.