Daily batterings from foot traffic and just the nature of clay-rich soil can compact the dirt under a lawn. When it comes time for a new lawn, tilling is the one step you should not skip. Turning over the surface of the old lawn helps to improve the growth of the final yard.
Tilling is done to aerate the lawn. This loosens the soil, making it easier for grass to grow. When installing a new sod or seed lawn, the old lawn must be removed to avoid contaminating the new growth. Tilling lifts up the old grass and turns it over while adding organic material and aerating the soil, improving its texture for the new grass.
When to Till
Before tilling your old lawn, you need to kill the existing grass. Covering the grass with a plastic tarp or a thick layer of mulch to block out sunlight and prevent photosynthesis is a natural method to kill the grass. Once the old lawn in dead, till it over into the soil. As the old grass breaks down into the soil, it will add organic matter, which will improve the appearance of your new lawn. In addition, don't till when the soil is too wet or too dry, particularly if it has a high clay content. Clods made by tilling wet clay soil can last for years, according to Colorado State University Extension, while dry soil will be too hard to till effectively.
What to Use for Tilling
For tilling, powered tillers are available for rent from garden centers or home centers. These are good to use if you have a large lawn that requires tilling or if you have heavy soil. For smaller areas, a rake or hoe can be used to turn over the dead grass and aerate the soil.
Cut 2-inch deep slices into the turf at regular, 2- to 3-foot intervals to break up the root structure of the old lawn. The soil needs to be lightly dampened before tilling, but not saturated. This helps the tiller to move through the soil without trying to move the excess weight of wet soil. Run a motorized tiller over the surface to turn the dead grass over into the soil. Ideally, you should till the soil 8 inches deep to create a loose soil structure for the new lawn. You might need to till twice over the lawn, passing the tiller over the yard at a right angle to the first tilling. Once tilled, add soil amendments to help the new grass grow before covering the yard with sod or seed.
- Toro Expert Guide to Lawns: Pro Secrets for a Beautiful Yard; Joseph Provey, et al.
- The Healthy Lawn Handbook; Lane L. Winward
- Black & Decker The Complete Guide to a Better Lawn: How to Plant, Maintain and Improve Your Yard and Lawn; Chris Peterson
- Colorado State University Extension: Soil Compaction
- Photo Credit Creatas/Creatas/Getty Images