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Get to the core of a healthy lawn: Time to aerate the soil

What to do with plugs of soil after aerating your lawn? Just leave them in place to naturally break down.
What to do with plugs of soil after aerating your lawn? Just leave them in place to naturally break down. Johnson County K-State Research and Extension

A healthy root system is a must for an attractive lawn. Oxygen in the soil is vital for strong grass roots. Our heavy clay and compacted soils commonly found in the Kansas City area often inhibit roots.

Core aeration improves rooting and problem soils without destroying the turf. Now is the time to perform this important task.

Core aeration improves the soil and grass by providing several benefits. It helps break up compacted soil caused by construction or traffic such as walking or kids playing. This miracle process also reduces the buildup of thatch, improves water and nutrient infiltration and adds oxygen while releasing carbon dioxide, all encouraging roots to push deeper into the soil.

Machines, slightly larger than a lawn mower, can be rented from many nurseries, hardware stores or rental agencies for a nominal fee. Commercial grounds maintenance firms also provide this service. Running a machine would be comparable to using a roto-tiller.

Aeration on bluegrass and tall fescue lawns is best done in the fall, September through October. Spring is also acceptable. For heavily compacted lawns, fall and spring aeration may be required. For the average lawn, once a year is all that is needed. Be sure the soil is moist in order to get the maximum benefit. A dry soil will inhibit the penetration of the hollow tines into the soil.

The holes that are made in the soil should be about 3 inches apart and 3 inches deep. The diameter of the holes made by the tines is about three-quarters of an inch. Several passes in different directions will be necessary to achieve the correct spacing. One of the most common problems seen with core aeration is the lack of multiple passes.

A common question associated with aeration is what to do with the plugs of soil removed from the ground that are scattered around the lawn. Just leave them in place to naturally break down. As the soil plugs decompose the soil naturally settles, helping to break down the thatch, renewing the lawn.

Aeration is an important part of a lawn care program. It should be incorporated with a total lawn maintenance plan or the benefits of aerating are of less value. There are no real physical signs to alert a person as to when the lawn needs aerating. Research has proved its value, so take advantage of this fall season to help improve your lawn.

Dennis Patton is a horticulture agent with Kansas State University Research and Extension. Got a question for him or other university extension experts? Email