September: Time to Core Aerate Cool Season Lawn

Soil plugs for core aeration

Traditionally September is considered the most important month for care of our cool season lawns, bluegrass and tall fescue. These grasses thrive in the cool of the spring and fall, and stress or even go into dormancy in the dog days of summer. The arrival of September with the milder conditions helps revive the summer stressed turf. It naturally wants to grow and thrive. This is why it is important we give the grass what it needs to fully recover from the stress of summer.

Time to Core Aerate

September is a good time to aerate your lawn as part of a healthy maintenance program. Aeration or core aeration is accomplished by a machine that can be rented or you can hire out the job. An aerator has tines or spoons that are forced into the soil and when they are removed pull a finger sized plug of soil out of the ground. This results in a number of benefits to the lawn.

Core aeration is the best way to help reduce soil compaction. It is the compaction of our heavy clay soils that halt deep root development and the movement of water and nutrients into the soil. This lack of strong, vigorous roots is what often time leads to a thin lawn which cannot stand up to the heat and drought of summer. Aeration is also the best way to keep that nasty thatch layer from developing which also effects rooting.

Like verticutting there needs to be good soil moisture so that the tines penetrate to a depth of at least 3 or more inches. Normally it is best to aerate in at least two directions so that the plugs or holes are about 3 inches apart. Research has shown this provides the greatest benefit.

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