Lawn Aeration Tips: Why, When, and How to Aerate Your Lawn

Whether you are a homeowner wanting to improve the look of your lawn, a garden enthusiast or DIY landscaper looking to learn new techniques, or even a lawn care professional wanting to up your game, understanding the importance of lawn aeration and how to do it, can improve both the look and health of the lawn under your care, making it lush and thriving for years to come.

Let’s take a look at the ins and outs of lawn aeration by covering:

• What lawn aeration is
• The importance of lawn aeration
• The best times to do it
• The different types of lawn aeration and how to perform them 

Lawn Aeration: What is it?

Before jumping into the why and how of lawn aeration, it is important to know what it is. So, what is aerating(pronounced “air rating”) a lawn? As the name suggests, aeration is the process of giving your lawn more air, much like opening a window to allow air to get inside. In this case, the inside refers to the soil, where your grass roots are. No lawn can thrive without healthy roots. Lawn aeration is a lawn care technique that supports a healthy root system.

The technique involves poking or slicing long, small holes into your lawn soil to allow for more oxygen to penetrate into the roots of your grass. You can think of it as a process that improves your lawn’s air circulation system so it can breathe better, getting stale carbon dioxide out and fresh oxygen in. This better circulation also makes it easier for the grass’ root system to get the water and nutrients it needs to remain strong and healthy. A healthy root system supports a healthy lawn. One that grows well and looks great. If that is what you are after, then aerating is a lawn care technique worth learning and applying. 

Lawn Aeration: Why do it?

If you are new to lawn aeration, you may be asking why you need to do it? It’s a good question with a fairly simple answer. By aerating your lawn, you give it a booster shot of the things it needs most, mainly oxygen, water, and nutrients, and helps keep it lush and healthy. All lawns can use this type of boost, but some are especially in need of the boost aerating can provide.

Signs that your lawn needs aeration include:

• The formation of patchy or thin spots of grass
• The grass is turning brown or dying
• Visible areas of soil compaction
• Puddles of water forming in random spots

If you want a great looking lawn, you most likely already carry out essential lawn care tasks, such as regular mowing, fertilizing, seeding, and watering. These all take care of the grass that grows to make up your lawn, but they do not necessarily take care of the soil that supports that growing grass. That’s where lawn aeration comes into play. Without good, healthy soil that supports good, healthy roots, it is difficult to have a great lawn.

The soil underneath your lawn can get depleted of essential nutrients if not replenished, which is why fertilizer is important. The grass, as you know, also needs plenty of water, oxygen, and sunlight. If your lawn grass, however, is riddled with thatch and the soil underneath is tight and compacted, it is difficult for nutrients, water, sunlight, and oxygen to reach deep into the grass’s roots, where it matters. These conditions usually are what cause the signs listed above. The remedy is often lawn aeration. 

Thatch Build-up

Undigested roots, leaves, and other organic plant material can build up and settle between your grass and the underlying soil, depriving it of the nutrients it needs to thrive. When this thatch gets too thick it can choke your lawn and make it start to look patchy and even die off. If you have thatch on your lawn that is more than a half-inch thick, it is especially important to aerate it. 

Soil Compaction

Soil compaction can be caused by several things and can be compounded over time, including: 

• Heavy foot or wheel traffic
• Walking on a wet lawn, especially after a heavy rain when puddles and mud can form
• Heavy equipment such as cars, trucks, or construction vehicles
• Activities that apply heavy pressure to the soil

When the soil underneath your lawn becomes compacted, it can cause any number of problems for your lawn’s root system. It makes it difficult for roots to grow deep and for the soil to carry the water, oxygen, and nutrients your grass needs to grow. It can also make it more susceptible to insects, pests, weed growth, and disease. Lawn aeration helps alleviate these issues by battling soil compaction. 

Lawn Aeration: When to do it?

The best time for yard aeration depends on your climate and the type of grass that you are growing. If your lawn is made up of warm-season grasses, such as Bermudagrass, Carpetgrass, Bahiagrass, or Augustinegrass, that thrive mostly in southern climates, you will want to aerate your lawn in late spring or early summer. By aerating earlier, you may promote weed growth.

If your lawn is planted with cool-season grasses, such as Kentucky bluegrass, Rough bluegrass, or Bentgrass, which thrive more in northern climates, then you will ideally want to aerate after fall hits. Late spring can work as well but could promote unwanted weed growth. 

With either warm-season or cool-season grasses, you want the grass to have time to grow and recover from the aeration process. 

When Should You Aerate Your Lawn in Minnesota?

With colder and harsher climate lawns, such as in Minnesota, lawn aeration is often an essential fall lawn maintenance task. It is best done once the weather cools with the start of fall but before the ground freezes. Depending on the weather, this can be anywhere from early to late autumn. In any case, you cannot aerate your lawn once the cold and snow sets in, which can be unpredictable in Minnesota, depending on the year, so doing it sooner in the fall is most likely better than later. Spring is also very short in Minnesota, where April snows are common. If Spring aeration needs to be done, it is best to think of completing the task around Memorial Day, which is the most reliable milestone for the ground to be thawed and the grasses growing. 

How Often Should You Aerate Your Lawn?

Lawns should be aerated about every three years to keep them lush and healthy, but if there are areas of your lawn that experience heavy traffic or the soil is especially heavy then annual aeration can be the key to keeping your lawn looking great. 

Lawn Aeration: Different Types of Aerators and How to Use Them

Learning the ins and outs of creating an aeration garden starts with understanding the different types of aerators that are out there and how to use them. With any technique, you should avoid aerating a dry lawn or an overly wet lawn. If the soil is too dry, the aerator will not be able to penetrate into the soil and if it is too wet the aerator may become plugged up. Your lawn should be well-watered a day or two before you aerate to give it time to dry out a bit, but still moist and firm.

Core or Plug Aeration

A core aerator has hollow metal tubes or tines that poke into your lawn and create long, small aeration holes by removing cores or plugs of soil and thatch. The holes created are about three-fourths of an inch in diameter. Core aeration can be either by hand or with a motorized machine aerator. The coring process reduces soil compaction and the newly created holes allow oxygen, water, and fertilizer to flow more easily to the grass’s roots.

This technique is particularly good for heavier soils, such as clay. If you have an extensive lawn, using a motorized core aerator can speed up the process and make it much easier. If your lawn takes up a smaller space and you do not mind the labor, then a manual aerator can be purchased for under $100 and often a lot less. If you opt for a motorized aerator, it is possible to rent one. As a homeowner you can, of course, also hire a lawn care professional.

When using a hand aerator, you will want to make sure to control the depth of the holes you are making. A typical depth of 2 to 4 inches is usually sufficient. You also want to space the holes apart across your lawn. It is best to have about 20 to 40 holes per square foot to properly aerate your lawn. A motorized core aerator can be calibrated to penetrate the lawn at an appropriate depth and remove plugs or cores spaced properly apart. A machine aerator though may not make enough holes for proper aeration, so a second or third pass across your lawn may be necessary.

The soil and thatch cores that are removed through the aeration process will be left on the surface of your lawn. After the aeration process is complete, it is a good idea to mow your lawn to break up the soil and thatch cores or plugs. You should also water your lawn every two or three days after aerating. A couple of days after core aeration is also an ideal time to seed your lawn, but do not wait more than a week to do so. 

After the core aeration process, your lawn may look disturbed and broken up. This look is only temporary. The point is for your lawn to not only bounce back but to look better than ever.

Spike Aeration

This type of aerator creates small holes in the soil of your lawn with a solid metal, wedge-shaped tine. One type of spike aerator is built mounted on a wheel, so to spike the lawn you simply roll it over the grass, much like a manual push mower. The spikes create a hole about 2” deep, but no soil or thatch is removed. There are also spike aerators that are worn more like shoes, so you create the spike holes by walking across the lawn. Spike aerators are best for sandy or loamy soil. If not done properly or in the wrong type of soil, spike aeration can make soil compaction worse, especially if watering closes up the temporary holes with compacted soil. 

The Last Word on Lawn Aeration

Whether you are a homeowner, landscaper, gardener, or a professional lawn maintenance provider you want the lawn under your care to be lush and healthy. Mowing, seeding, watering, and fertilizing are regular tools in your lawn care toolbox. Adding lawn aeration is another technique worth applying to achieve the lawn you want.