Lawn aeration helps by improving microbial activity, increasing water, oxygen and nutrient movement into the soil, improving rooting and reducing pesticide and fertilizer runoff. Generally these benefits come from reducing soil compaction, which can be a problem for residential lawns.
Lawn aeration involves the removal of small soil plugs or cores out of the lawn. Although hand aerators are available, most aeration is done mechanically with a machine having hollow tines or spoons mounted on a disk or drum.
Known as a core aerator, it removes 1/2- to 3/4-inch diameter cores (or plugs) and deposits them on the lawn. The holes left are typically 1 to 6 inches deep and 2 to 6 inches apart. There are aerators with solid tines which push their way into the soil. These are not as desirable as they may actually contribute to compaction of the soil rather than help it.
Generally, at least for our area, the best time to aerate cool season lawns of tall fescue and Kentucky bluegrass is in late August to mid-September. In a normal year, these lawns will be coming out of summer dormancy and beginning a period of vigorous growth. Due to the dry weather, we really haven’t seen that period of vigorous growth until recently. If you didn’t get it done this fall or have never aerated, you might plan on doing it next spring if you feel you have a compaction problem and if not you can wait till next fall.
Successful aeration involves aerating when the soil is moist but not wet. If it is too dry the tines will not penetrate the soil to the proper depth. If it is too wet the soil will not fall out of the tines. If you have to irrigate, put down at least one inch of water two days prior to aeration. Aerate the lawn in two different directions to insure good coverage. Mark and avoid underground wires, water lines, invisible fences, tree roots, rock ledges and other things that could either damage or be damaged by the aerator. Dragging a piece of chain link fence over the cores will help disperse them back into the soil.
Most people do not own an aerator nor do they need to. Check with your local rental store. If you need more information on this, contact your local Extension office.
Phil Blevins is an agricultural extension agent in Washington County, Virginia.