If your lawn is not looking good, you may want to consider lawn aeration. But is lawn aeration necessary? This is a question that sometimes causes heated discussions.
First it may be best to answer the question, what is lawn aeration? Aeration simply creates holes in the lawn. It removes cores of compacted soil, making space for air, nutrients and water. Lawn aeration can be done manually or by using a power aerator. Note that in lawn aeration the cores are typically about half an inch thick and three to five inches long.
There is another form of aeration, sometimes called spike aeration. Spike aeration is done by pushing solid spikes into the lawn. It is not as efficient as lawn aeration which removes cores of soil. The spikes only make holes in the lawn, they don’t remove any cores. We recommend that you stick to real lawn aeration and forget about spike aeration.
So how does aeration help your lawn? The main reason for lawn aeration is to combat soil compaction. Soil compaction happens mainly because of the traffic, both vehicle traffic and foot traffic, which simply put pressure on the lawn. According to research, freeze-thaw cycles don’t loosen compacted soils, it is just a myth. Soil compaction will slow the growth of your grass. By aerating the lawn you invigorate the soil.
As mentioned earlier, lawn aeration can be done manually or by using a machine. Manual lawn aeration is simple to do but is not really feasible unless you have a small lawn. For larger lawns, it is better to rent a power aerator. Buying one can be difficult to justify financially. You are unlikely to use it more than once a year. If you have a tractor, you can buy or rent an aerator attachment instead.
Manual lawn aeration is done with a tool that consists of two or more hollow tubes attached to a stirrup. You put your foot into the stirrup and force it down into the lawn. The power aerator is used like a lawn mower, it jams its tines into the soil as you steer it over the lawn.
You should aerate your lawn when the soil is moist but not wet. Dry or wet soil makes the aeration cumbersome. If the soil is wet, the cores are likely to get stuck in the tines. If the soil is dry, it is more difficult to penetrate. Note that the cores can be left on the surface of the lawn, they will decompose within a short period of time.
Back to the original question, is lawn aeration necessary? Yes, in most cases you should consider to aerate your lawn. But for most lawns doing it once a year is good enough. Often it is enough to aerate the lawn once every second year. The best time to aerate cool-season grass is early fall or late summer. Warm-session grass is best aerated in the spring. Note that lawn aeration can be done at any time, except for when the soil is frozen.