A healthy root system is a must for an attractive lawn, and oxygen in the soil is vital for a strong root system. The heavy clay and compacted soils commonly found in the Kansas City area often inhibit roots. Core aeration improves rooting without destroying the turf. Now is the time to perform this important task.
Core aeration improves the soil and grass by breaking up compact soil caused by construction or foot traffic, reduces the buildup of thatch, improves water and nutrient infiltration and adds oxygen while releasing carbon dioxide. All help roots push deeper in the soil.
Machines, slightly larger than a lawn mower, can be rented from nurseries, hardware stores and rental agencies. 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 breakdown 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.
Dennis Patton is a Johnson County Extension horticulture agent. To get your gardening questions answered by him, go to kcgardens.kansascity.com.