Did you know that 25% of the soil should be air? It’s important that the root zones of plants, is able to exchange gasses with the atmosphere to help keep the grass plants healthy. More air in the soil gives earthworms and other beneficial insects and organisms more room to move and grow, helping keep your lawn naturally healthy. Better absorption means that fertilizers can reach the lower root zones of the grass plants, keeping them from only forming surface roots that can wither and die during a drought. Let’s help this process along by learning how to aerate lawns.
When to Aerate
If you've noticed that rainwater isn't absorbing into the soil surface, have clay soil or have a lot of traffic on your lawn, it may need aeration up to twice a year just before the grass begins to grow again, though not in the first year after planting. Cool season grasses like bluegrass, fescue or rye grasses do best being aerated in August, just before they begin fall growth; warm season grasses like bermuda, buffalo and zoysia grass do their best being aerated from April until June, depending on your climate. Today we’ll explore the tools and techniques used in aerating your lawn to keep it healthy.
Tools Used in Aeration
When learning how to aerate lawns, there are two tool types used, one using spikes to create holes down into the soil surface, and the other removing cores from the soil using a cylinder to cut them. Spike aerators tend to not have as long an effect on the soil and can sometimes worsen compaction, so you’ll want to stick to the coring variety. Be sure to get an inch of water onto the lawn a day or two before you’re going to aerate, especially on clay soils, as this will make it easier for the coring tools to work.
You’ll want to cover the ground two to three times, so stick to a back-and-forth pattern that helps you see where you’ve been when you’re learning how to aerate lawns, then change direction to perpendicular to the original path.
Safety first! Before starting, know the location of any close to the surface wiring, irrigation lines, telephone lines and similar issues. Be sure to be aware of where any small children or pets are, as well as the path the aerator is going to take.
Manual Aeration Tools
A hollow tiner resembles a two-handled pitchfork, with hollow tines to remove soil cores. You’ll want to insert it into the soil to a depth of about 3″, remove it, move about 4″ and repeat, going over the lawn at least twice in perpendicular directions.
Powered Aeration Tools
If manually aerating the soil sounds like too much work, you can check local rental companies for powered aeration equipment. You’ll want to find an aerator that has cores 1/2″ to 3/4″ in diameter, 2″ to 3″ deep and 2″ to 3″ apart. If it has some additional weight behind the tines, it will be able to get through the soil more easily. You may want to try to rent on a weekday or plan to make reservations early as many people will want to rent this equipment on weekends. Be sure that you have a good understanding of how the machinery works before leaving the rental company.
Another idea is to work with several neighbors, renting one machine and then taking care of everyone’s needs at once. This can be especially helpful if you've got a neighbor with a larger truck or trailer and tow vehicle who can pick up and drop off the machine.
If you have a large area of yard or pasture to aerate, you may want to look at picking up an aerating attachment for your lawn or garden tractor, especially if you can make back part of the cost by taking care of neighboring yards as well.
After You’re Done
Once you've finished, it’s up to you whether you want to rake up the cores or leave them to disintegrate and rejoin the soil matrix; they’ll add organic matter back into the soil which increases its ability to hold water and nutrients. This is also a great time to add seed, compost and fertilizer for the best penetration. Some landscaping professionals recommend spreading sand on heavy clay soils, as it will fill the holes and will help keep the cores open to the air longer.