Can You Lay Sod Over Grass?

Existing Lawn

• Installing sod is similar to transplanting other types of plants. For the sod to grow, the roots require contact with the soil. Planting sod over an existing lawn prevents this necessary contact. You can solve this problem by creating a new layer of topsoil or removing the existing lawn.

New Topsoil

• Placing a barrier over the old lawn and adding a new layer of topsoil is only suitable in areas where doing so won't disturb the proper drainage grade of the land. This process involves placing overlapping layers of biodegradable material such as cardboard or newspaper over the existing lawn, covering with mulch or compost, then spreading at 4 to 6 inches of topsoil over the buried grass.

Removing Old Lawn

• Sod removal is the basic method of replacing an old lawn with new sod. The existing grass, including the roots, needs to be cut out. A sod cutter is a tool that quickly slices through roots and separates the grass plants from underlying topsoil. Watering the lawn 24 to 48 hours before removing the old sod will soften the soil and simplify the process.

Soil Preparation

• A soil test is an important first step in growing a new lawn from seed or sod. A soil test reveals any nutritional deficiencies that can be cured with amendments to support the growth of your grass. Organic matter in the form of compost will help loosen compact soils and replace missing nutrients.

Soil Aeration

• Lawns, especially old ones, tend to compact the underlying soil. Breaking up the bare soil with a garden tiller helps aerate and loosen the planting site. Tilling also helps uproot any remaining roots from the previous lawn grass.