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…
Should you plant a clover lawn? Read this first
How to know if a clover lawn is right for you
White clover flowers

The classic grass lawn has a certain appeal to it, but it isn’t for everyone. If you’re looking for something more sustainable, eco-friendly, or just more interesting than an all-grass lawn, you might be considering a clover lawn. We’ll help you decide if s clover lawn id right for you, or if your lawn is better suited to grass or a mix of grass and clover. No matter your reason for being interested in clover lawns, we’ll answer as many of your questions as we can in this handy guide to clover lawn care.
What are the benefits of clover lawns?

Clover lawns have benefits for you, your local ecosystem, and your soil. Clovers are nitrogen-fixing plants, meaning they add nitrogen back to the soil overtime, which is good news if you ever decide to plant something else in your lawn. Clover is also easier to plant and maintain than grass. It needs less mowing, fertilizing, and watering than most types of grass.

Read more
Not sure what growing zone you’re in? This is how to find out
The USDA hardiness zone you live in is important
Herbs in nursery pots on a table with a watering can, gloves, and gardening tools

If you’re asking, "What growing zone am I in?" you’re not alone. This is especially true since the USDA updated the hardiness zone map in November 2023. This was the first major update to the map in over a decade, and it’s understandable that it caught some gardeners by surprise! So, if you’re curious or confused, this guide will help clear things up. We’ll explain why the zones changed, how to tell what zone you’re in, and why growing zones are important.
Why did the USDA change the growing zone map?

The USDA hardiness zone map hadn’t changed in over a decade, so why was it updated in 2023? In short -- climate change. The map is only useful as long as it accurately reflects the climate in each area, so as the climate shifts, the map has to shift with it. This is especially true since the zones are determined by winter temperatures, which climate change heavily impacts.

Read more
5 incredible deer-resistant flowers you need to know about
Plant these flowers to keep deer away
A deer in a field of purple flowers

Growing a gorgeous flower garden can be such a fulfilling and rewarding hobby. There are a near endless number of ways to express your creativity through your garden. However, it can be incredibly frustrating to spend time and energy planning and caring for your garden only to find it razed to the ground by deer.

Deer are a native species, and they are both cute and important for the health of the ecosystem, but that doesn’t mean you should just sit back and let them eat your garden! Plant some of these deer-resistant flowers to keep them at bay instead.
Daffodils

Read more