Core Aerator: Three Main Types
As part of regular lawn maintenance, aerating with a core aerator is essential to growing healthy, drought- and disease-tolerant grass. Lawn core aeration should be done every one to three years depending on how dense and compacted the soil is and how quickly it re-compresses. Core aerating puts holes in the soil that allow the roots of the grass to get the nutrients, water, air and sunlight they need to grow deep and maintain the health of the grass. There are three main types of core aerators: manual, fuel-powered and tow-behind.
A manual core aerator consists of a long pole with two or three hollow prongs on the bottom attached to a crossbar. You step onto the cross bar while holding the handle at the top and push the prongs into the ground. As you pull it up, the dirt plugs come out and land on the lawn and you continue to the next spot. These lawn core aerators are inexpensive, but time-consuming to use. It would take most people a few days to do a large lawn. This type is best for small yards, for doing touch-ups after or in-between other core aerating, or for someone who does not mind the additional work and time involved in this method.
Core Gas Aerators
Mechanical core aerators are typically powered by gas, similar to gas lawnmowers. Typically you walk behind them across the lawn in long rows, putting in holes and pulling up dirt cores as they go. They are very heavy and it can be tricky to turn them at the end of a row to go back the other way. Some newer ones have features that make this easier. Split tines, where each half is controlled separately, allow the operator to turn the machine with some tines still in the ground. Others have power-lift controls requiring less manual effort to re-position the aerator.
Tow-Behind Core Aerators
Tow-behind models either attach to a gas-powered lawn mower or a tractor. Their tines are attached to a cylinder that pushes and pulls them in and out of the ground as they are towed along. They tend to be wider and trickier to move across the lawn, but they also aerate the fastest with the most holes and the least amount of manual work. They are the best for the most heavily-compressed soils since they get into the ground deeper and better and can easily take on additional weight to improve penetration and hole depth.
Choose the type of aerator that is best for your lawn, but stay with the core aeration for the best job. Aerate early or late in the grass growing season, so the lawn will still get plenty of water and time to bounce back from the stress it causes the turf. With the roots exposed, it is a good time to apply soil conditioners or fertilizers to further improve the grass health. Over seeding is also good to do right after lawn core aeration.