How to Aerate a Lawn

close-up of a core aerator machine

Aerating a lawn isn’t difficult, but this lawn care chore can be time consuming to do it right. In this guide we’ll show you how to aerate a lawn, benefits of aeration, and types of aeration. 

We’ll even detail when is the best time of the year to aerate your lawn. Hint: That depends on your grass type. 

First, though, what is aeration and how does it help your lawn? 

Aeration creates holes in compacted soil so air, nutrients, and water can reach your grass’s roots. When the soil is too compact, your grass won’t have optimal access to the vital resources it needs to flourish and be as green as it can be. 

How to Aerate Your Lawn (in 7 Easy Steps)

1. Choose an Aerator Tool

The first step to aerate a lawn is to choose which tool you’re going to use. There are different ways you can perform core aeration and spike aeration. (Unfamiliar with the types of aeration? Jump to Core Aeration vs. Spike Aeration, then scroll back up here.)

Manual core aerator: Like pressing your foot on a shovel, you use your foot to push a manual core aerator into the ground. The soil travels through hollow tines and pops out as a 2- to 3-inch-long plug (kind of like super-thick Play-Doh spaghetti). Using a manual core aerator on a large yard may prove tiring and time-consuming. 

Push-behind core aerator: This tool is excellent for aerating a large yard. You push this kind of core aerator like a lawn mower, and there are gas- and electric-powered versions.. Many home-improvement stores offer hourly, daily, or weekly rentals of push-behind core aerators. 

Tow-behind core aerator: If you don’t want to press down on a manual core aerator or push behind a core aerator, you can attach a tow-behind core aerator to your lawn tractor. 

Manual spike aerator: Pitchforks and spading forks make good manual spike aerators. They may even be in your garden shed, making a pitchfork or spading fork an easy solution for spike aeration. 

Spiked aeration shoes: You attach these spiked “sandals” to your shoes and walk around your yard to create tiny holes in your lawn. This spike aeration method might appear fast and easy, but it does take energy to press the spikes into the ground. 

Rolling push aerator: The spikes on a rolling push aerator rotate and pierce holes into the ground as you push this tool across your lawn. 

Tow-behind spike aerator: To spike aerate a large area with ease, attach a tow-behind spike aerator to the back of your lawn tractor. 

2. Call Before You Dig

Before you dig in your yard, call 811 a few days beforehand. Calling in advance gives utility workers plenty of time to flag or paint areas where underground utility lines are. Avoid aerating these areas. 

3. Irrigate the Lawn

Water the lawn with 1 inch of water one or two days before you aerate to help soften the soil. Here’s why: Aerating bone-dry soil is less effective and will give your arms or feet more of a workout if you use a manual core aerator or spiked aeration shoes. 

But don’t overdo the watering ahead of aeration.

If the soil is wet on the day you plan to aerate, wait another day. Aerating wet soil creates a muddy mess, which can ruin your tools and defeat the whole purpose of aeration. Why? Because the mud will close up the aeration holes.  

4. Flag Sprinkler Heads

Before you aerate a lawn, flag your sprinkler heads so that you know where they are. The last thing you want is for your aerator to knock out your new (and expensive) sprinkler system

5. Aerate the Entire Lawn

Aerate your whole lawn, not just spots. Criss-cross your yard as you do when sowing seed or mowing your lawn. Check that your aerator tool is making holes and popping up plugs of soil. With a manual aerator, you’ll need to keep an eye on the distance between your holes. With other aerators, you may need to repeat the process if your soil is highly compact.

For example:

If you’re using a manual aerator –– such as a pitchfork or manual core aerator –– ensure the aeration holes are 2 to 3 inches deep and roughly 3 inches apart across the entire lawn. 

Guide your push-behind aerator across the lawn like you would a push lawn mower. If your soil is severely compact, aerate the lawn a second time in a perpendicular direction, as if you were creating a grid. 

If you use a tow-behind aerator, attach it to your lawn tractor and begin aerating your lawn. If your soil is tightly compact, you may need to aerate the yard a second time in a perpendicular direction. 

6. Leave Plugs on the Lawn

If you used a core aerator, you don’t need to remove the plugs in your yard. They’ll eventually dry and crumble, reintroducing organic matter into the soil. It takes about two weeks for plugs to break down. 

7. Apply Soil Amendments or Overseed

Now that aeration has exposed more of your lawn’s soil, it’s a good time to add any necessary fertilizer, compost, or overseed with grass seed (if needed). 

manual spike lawn aerators that fit over your shoe, sitting on grass
Photo Credit: Shutterstock

Core Aeration vs. Spike Aeration

Core aeration vs. spike aeration? In a nutshell, your lawn will likely benefit more from core aeration than spike aeration. 

Here’s why: Spike aeration offers a short-term solution for compact soil, whereas core aeration offers a long-term solution. And unlike core aeration, which relieves compact soil for the whole yard, spike aeration can increase compaction in certain spots. 

Core Aeration 

So, why is core aeration often preferred for long-term success? It comes down to how the aeration holes are made. 

Here’s core aeration works: Core aeration creates holes by removing plugs of soil from the ground. The holes in the soil allow air, water, and nutrients to reach the roots, and the roots can grow into the open space. 

A core aerator’s hollow tines are about three-quarter inches in diameter and can penetrate the soil about 2 to 3 inches deep. 

How core aeration reduces compaction: Imagine your lawn as a crowded room where people are bumping into one another, elbows are hitting ribs, and it’s a challenge to breathe. Core aeration ”’relieves” the crowded space by removing people from the room. With fewer people in the room, everyone has a bit more space to stretch their arms and breathe easier. 

Spike Aeration

Why do some homeowners prefer spike aeration? It’s a quick solution. 

Haven’t got time to rent an aerator, but your lawn is showing signs that your soil is compacted? Run into the garden shed and grab your spading fork and poke a few holes in the ground. The holes will create space for water, oxygen, and nutrients, but only for the short term. 

How spike aeration works: Spike aeration relieves compact soil by poking holes in the ground. The holes will create space for water, oxygen, and nutrients, but only for the short term. 

Here’s the drawback: Spike aeration pokes holes in but doesn’t remove any soil. Instead, the aerator tool’s (or shoes’) solid tines push the soil further into the ground and toward the sides.  

The spikes ultimately create small pockets of space while increasing soil compaction around the sides of the holes. The compact sides around the holes still block a significant amount of air, water, and nutrients from reaching the roots. 

Not sure how spike aeration increases compaction? Let’s look at the crowded room example. 

How spike aeration increases compaction: Imagine if people in the room created small pockets of open space by squishing themselves closer together. No one removes themselves from the room, which ultimately makes the room feel more crowded (and compact) than before, despite the free space. 

Benefits of Core Aeration

You know that core aeration is an important lawn care task, but how does it benefit your lawn? 

5 Ways Core Aeration Helps Your Lawn

  1. Enriches the soil: When soil becomes compact, it squeezes so tight together that water, oxygen, and nutrients can’t move through the soil. Aeration creates small holes to allow oxygen, nutrients, and water to penetrate the soil.
  2. Improves root growth: Grass roots struggle to develop in compact soil. The aeration process loosens the soil and encourages root growth.
  3. Reduces thatch buildup: Lawn aeration penetrates thatch and helps minimize its buildup. Thatch is the dead and living organic matter that accumulates between the soil surface and the grass blades. When thatch becomes too thick, it blocks water, nutrients, and air from reaching the soil. 
  4. Benefits earthworms: Compact soil makes it difficult for earthworms to perform their beneficial duties. For example, earthworms help control lawn thatch, but compact soil impairs their ability. When thatch is left unchecked, it creates a breeding ground for pests and disease. 
  5. Lessens drainage issues: When compact soil blocks water from seeping into the ground, this causes drainage issues. Puddles, runoff, and soil erosion are less likely to occur after aeration. 

When to Aerate Your Lawn

The best time to aerate your lawn is during your grass’s active growing season. Aeration is an invasive treatment, and your grass will heal best when the grass is actively growing. 

If you grow warm-season grass, such as Zoysia or bermudagrass, the best time of year to aerate the lawn is in summer.

If you grow cool-season grass, such as fescue or Kentucky bluegrass, the best time of year to aerate the lawn is fall.

FAQ About Lawn Aeration

1. How often should I aerate my lawn?

If your lawn has heavy clay soil, you may need to aerate it once a year. If you have sandy soil or your soil doesn’t compact easily, aerating once every three years usually is enough. 

2. What are some signs my lawn needs aeration?

These are common symptoms or indications your soil is compact: 

— The grass is thinning or turning yellow
— Puddles form in low areas of the yard
— Water quickly runs down elevated areas of your yard 
— Your grass grows slowly or not at all
— Your yard has patches of bare soil where weeds and grass won’t grow
— Your lawn has a thick, spongy thatch layer
— Your lawn has frequent pest and disease problems
— It’s challenging to stick a screwdriver in the soil

3. What causes compact soil?

Compaction occurs when the soil particles are squeezed together, and the pore space reduces.

Here are some common causes of compact soil: 

Heavy traffic over the lawn from people, pets, equipment, or vehicles
A construction project recently was completed on the property
High precipitation levels or overwatering
Your soil has a high clay content (See our Guide to Soil Types)
Over-tilling the soil, especially when it’s too wet or too dry
Mixing sand into clay soil (this can give your soil a concrete texture

4. How can I prevent compact soil?  

Install walking paths that redirect foot traffic away from the grass
Don’t park or drive cars or heavy equipment over the lawn
Don’t under-water or over-water your lawn. (Perform proper irrigation)
Don’t over-till the soil. If you need to loosen the soil, add organic matter such as compost, leaf mold, or peat moss instead of sand. 
Change mowing patterns often or opt for a lightweight lawn mower. 

Another Option? Hire a Pro for Lawn Aeration

Aerating a lawn isn’t difficult, but this lawn care chore can be time consuming to do it right – especially if you use a manual core aerator. If aerating your lawn isn’t how you want to spend a couple of hours (or more), hire a LawnStarter lawn care pro to do it for you.

How much does aeration cost? Well, that depends on the size of your yard and the method you use, but lawn aeration costs between $65 to $239, with most homeowners paying $174.

Main Photo Credit: Shutterstock

Jane Purnell

Jane Purnell

Jane Purnell is a freelance writer and actor in New York City. She earned her B.A. from the University of Virginia and enjoys a warm cup of French press coffee.