It’s a good time to aerate the lawn

Published 12:00 am Friday, September 11, 2009

By Darrell Blackwelder
Cooperative Extension
Recent rains have been a welcome sight for those renovating lawns this fall, especially those who want to core aerate their lawns.
Tight clay soils in the Piedmont are virtually impossible to effectively aerate during periods of dry weather.
Core aerating is an important part of lawn maintenance, especially for renovation of fescue lawns. Core aerating pulls a portion of soil out of the ground, providing an open space about a half inch wide and 3 or 4 inches into the soil. The only disadvantage is the casting left on top of the soil.
Spike aerators punch holes into the soil and leave no casting. This may be a desirable result of spiking, but spiking is not recommended because the spikes actually compact the soil. The core casts from the aerator melts away in a few weeks.
Increasing soil air space is important to growth and expansion of fescue and bluegrass root systems. Coring also allows fertilizers and lime quicker access to the plant’s root system. Soil tests that call for extra phosphorus benefit from nutrients placed in the root zones. Clay soils with low pH often inhibit uptake of phosphorus, which is tightly bound in the upper layer of soil.
Those who want to renovate fescue lawns can core aerate, fertilize, lime and seed on the same day. Coring is also an excellent alternative to plowing a lawn that needs to over-seed. Be sure to aerate first before adding seed and fertilizer. Those with bare or weak stands will benefit by adding straw mulch to maintain sufficient moisture levels.
Core aeration should be done every other year on well established lawns. It’s best to avoid coring in the spring since newly formed roots are damaged and it provides an open wound in the lawn for weeds to germinate. Lawns that are weak and thin can be cored on an annual basis until the desired stand is achieved.
Equipment rental dealers generally rent core aerators for about $75 day for the power walk-behind type or the towable pull behind the tractor rents for approximately $45 a day. Those that rent the self-propelled core aerator won’t have to go the gym that day. These machines will give you a workout ó trust me. Those with physical limitations should consider hiring a lawn care company.
Darrell Blackwelder is an agricultural agent in charge of horticulture with the North Carolina Cooperative Extension Service in Rowan County; call 704-216-8970.