A smooth expanse of lawn is a refreshing garden feature. Poorly planted lawns develop bumps and depressions in need of levelling. Grassy areas subjected to heavy usage or improper care need restoration. Spots damaged by animals, chemicals, disease or furniture placement need refreshing. Levelling a bumpy lawn or refreshing a damaged area can be as simple as spreading topsoil over the existing grass.
A healthy lawn in need of levelling is easily addressed by spreading topsoil over the surface and levelling the top. Grass fills in within a few weeks during the growing season. For small spots, a bag of topsoil spread over the area, raked into the sod and levelled corrects the problem. Large areas are spread with topsoil and levelled with heavier equipment. A chain link fence section dragged behind a truck or tractor is effective for acreage. Reseed where the fresh soil layer is too deep or wide for the existing grass to fill in.
Thatch is an organic spongy layer above the topsoil surface that develops as the lawn grows. Eventually, this layer of dead and living grass becomes devoid of soil, strangling new growth by depriving it of oxygen, nutrients and water. The entire lawn becomes drought-stressed, even in the presence of adequate irrigation. Thatch builds up more quickly in some grasses. Kentucky bluegrass, bentgrass and fine fescue are especially subject to develop problem thatch. A layer of thatch less than 1/2-inch thick is controlled through power raking, aerating or core cultivation. Topsoil spread over a thick layer of thatch is useless.
Spreading topsoil over a badly damaged existing lawn is ineffective when excessive thatch build-up, disease or neglect has resulted in a soil surface incapable of supporting healthy new growth. The entire lawn or significant areas need renovation. Spots damaged with chemicals or disease must be dug out, the soil replaced and reseeded. The approach to renovation, whether to do it yourself or hire a professional, depends on factors such as the size of the lawn and available resources.
A Smooth, Healthy Lawn
Beginning with healthy soil and suitable grass varieties contributes greatly to a smooth, long-lasting lawn. Select grass varieties or seed mixtures suitable to your growing locale. Prepare the site carefully by removing weeds and improving the existing soil as necessary. A soil surface that is smoothed before seeding results in a smooth, level lawn. Sod laid over a healthy, level soil surface results in a quickly available lawn. Consult your local county extension service for guidance. Small uneven areas are easily repaired by adding topsoil if the lawn is healthy and well-cared for.