Skip to main content

When should you aerate your lawn? What you need to know

When your grass starts growing unevenly, thinning out, or changing color, such as turning yellow, it very likely means it needs aeration — even if you’re feeding it regularly. Unsightly symptoms can occur when you have tightly compacted soil because neither the roots nor the water can penetrate it. Core aerating may sound like a miracle cure for your lawn, but it can do wonders. Keep on reading to learn more about this process and when to aerate your lawn.

A lawn with several rows of small holes

How does an aerator work?

There are several kinds of aerators, but the hands-down best results come from core aerators. A core aerator is a heavy roller covered with hollow spikes that roll across the grass to pull soil plugs from the lawn’s root zone. The sheer weight of the roller drives the spikes through layers of thatch, dense roots, and compacted soil. It pulls 3/8 inch diameter plugs, up to 3/4 inch deep or more.

Recommended Videos

The aerator functions best on damp soil. Hard, dry soil may be impervious even to the machine that’s supposed to fix it. While you might be able to fix this by lightly irrigating several times per day for a week to soften the soil, a better solution would be to aerate after a significant stretch of wet weather.

What does aeration do?

If your grass looks bad, aeration could be one of the keys to bringing it back to good health. Hardpan soil resists water penetration and deep root development. Some grasses adapt to this condition by forming a dense layer of shallow roots, rhizomes, and stolons at the soil surface, better known as thatch.

Aerating the lawn addresses thin and bare spots associated with soil compaction, and it helps correct thatch buildup caused by shallow rooting. Aerating the lawn loosens the soil surface and breaks up the thatch layer, which fosters deeper root development. It also lets water and nutrients penetrate deeper.

How do I know if my lawn needs aeration?

Lawn aerating shouldn’t be viewed as a routine maintenance activity. Aerating the lawn when it isn’t necessary weakens the grass and could lead to pest or disease problems. Instead, watch for indications of compact soil, such as worn areas, puddling, thin or dead patches, discolored grass, uneven growth, or thatch buildup. Any one of these symptoms could indicate the need to aerate.

If you think your yard needs to be aerated, perform a screwdriver test. Using any type of screwdriver with a 6-inch blade, attempt to push it into the soil. If you meet with some resistance, it could be time to aerate. If you can’t push the blade into the soil all the way up to the handle, you should definitely aerate the lawn.

It would also be helpful to aerate before overseeding the lawn. Mow the grass low, then aerate the yard prior to applying lime, fertilizer, and seed. Doing so will help the grass seed stay put if it rains before germination. It also helps to promote healthy root development.

Close-up of plug aerator
Image used with permission by copyright holder

When should I aerate my lawn?

When you aerate the lawn, you sever many feeder roots and weaken the plants. It’s best to do this as the grass heads into a strong, rapid growth phase. Aerating too early or late in the year, such as during winter dormancy or summer heat and drought, stresses the grass at a time when it needs to conserve its resources. Poor timing of aeration could open the lawn to weeds, insects, or disease.

The best time to aerate a lawn is at the beginning of its rapid growth phase. For warm-season grasses like Bermuda grass and zoysia grass, that means shortly after it turns fully green in late spring or early summer. Cool-season grasses like tall fescue and Kentucky bluegrass are best aerated in either early fall or early spring.

Is aerating your lawn worth it?

Aerating the lawn is definitely worth the trouble and the expense if your lawn is in need of aeration. Lawns with the classic symptoms, such as thinning, discoloration, or uneven growth are likely candidates. It also makes sense to aerate before overseeding.

There’s no need to contract with a landscaping company to aerate every spring. Instead, add a lawn inspection to your to-do list each year. Pay close attention to worn areas, low spots where puddles form, discolored patches, and areas of uneven growth, and perform the screwdriver test as described above. If your lawn fails the screwdriver test, then it’s time to aerate your lawn.

Mark Wolfe
Former Digital Trends Contributor
Mark Wolfe is a freelance writer who specializes in garden, landscaping, and home improvement. After two decades in the…
Why you shouldn’t grow eucalyptus trees in the U.S. (and what you can grow instead)
What you can plant in place of a eucalyptus tree
Tall eucalyptus trees

Trees are a major part of our ecosystem. They provide shelter and food for wildlife, absorb carbon dioxide and produce oxygen, and provide shade to help keep us cool. However, not all trees have the same benefits, and some do more harm than good. If you have a eucalyptus tree in your yard, or are planning on getting one, then you should be aware of the dangers these beautiful trees can pose. If you’re wondering what the big deal is, this guide to eucalyptus trees will explain everything.
Why shouldn’t you plant eucalyptus trees?

There are many reasons why planting eucalyptus trees is a bad idea. First, eucalyptus trees aren't native to the U.S., and they carry more danger than some of the more common invasive species. Typically, the concern with invasive species is that they might spread rapidly and out compete native species, changing the natural ecosystem in a way that's difficult to reverse. Eucalyptus trees can spread, and they do grow quite quickly, but there are larger problems when growing them.

Read more
When and how do bananas reproduce? All your questions answered
Everything you need to know about how bananas grow
Banana tree with ripe fruit

Bananas are delicious, versatile, and full of nutrients our bodies need. They're enjoyed by both people and animals, and although they may not be the first fruit you think of when planning your garden, you can in fact grow them at home. If you’ve ever eaten a banana, though, you may have noticed that they don’t have seeds like an apple or orange.

You may be left wondering about how bananas reproduce. Do they actually have seeds after all, or is there another way to propagate them? If you aren't familiar with bananas, it can be frustrating to try and figure out what to do when you want to propagate them. To help you feel more prepared, we've put together this handy guide of everything you need to know about how bananas reproduce.
Where do bananas come from?

Read more
Can potting soil go bad? The signs and solutions you should know
How to tell if your potting soil is still fresh
Hands holding soil

Container gardens are a great way to get into gardening if you’re low on space or time or just aren’t sure if you’d enjoy having a full-sized outdoor garden. Many plants can grow in containers, and there are so many fun and creative container options you can choose from.

No matter what plant you’re growing or what container you choose, there is one thing that all container gardens have in common: potting soil. If you’ve ever bought a bag of potting soil for a project that ended up delayed, you may be staring at that bag wondering, "Can potting soil go bad?" Here’s what you need to know.
Can potting soil go bad?

Read more