As you get more and more involved with taking care of your lawn, you start to hear different terms, such as aeration. I think all of us lawn enthusiasts have a pretty good understanding of the ins and outs of aeration, but if you are new to this topic, then you might be asking yourself, what is lawn aeration? Well, let’s dive into aeration and see what all the fuss is about.
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What is Lawn Aeration (Overview)
Lawn aeration is a lawncare practice designed to reduce the negative effects of soil compaction. Aerating equipment such as core and spike aerators are designed to puncture the soil in order to improve drainage, nutrient availability and allow air exchange. Without aeration, the roots of a lawn are starved and suffocated of vital resources needed to grow and thrive.
A Closer Look at Lawn Aeration
Before we jump into lawn aeration, let’s look at what aeration is trying to fix: soil compaction. Knowing the problems caused by aeration will help you better understand the solution.
What is Soil Compaction?
Soil compaction is the process of soil being compressed, increasing soil density. For example, if you squeeze a hand full of dirt, you compress the soil particles, which in turn squeezes all the air out and compacts the particles closer together. As a result, water, air, and nutrient have less space to pass through. Another example would be comparing sand to clay. Sand is significantly less dense than clay, meaning sand is more porous and absorbent. Again this is due to the level of density of the material.
Why Should You Aerate a Lawn?
So what does soil compaction mean for your lawn? Well, if your lawn has excessively compacted soil, you’ll start to see a decline in your lawn’s health. Here are a few of the biggest issues soil compaction can cause for your lawn.
Lawn Issues Caused by Soil Compaction
- Reduced Water Absorption
- Limited Nutrient Access
- Limited Nutrient Intake
- Restricted Air Exchange
- Poor Root Growth
- Reduced Drainage
Reduced Water Absorption
Soil compaction reduces the passageways within the soil, reducing water’s ability to absorb into the ground. As a result, even though your lawn is getting plenty of water, unfortunately, it cannot reach the roots. However, using soil aeration to break up the soil will restore the necessary pathways for water to gain access to the roots of your lawn.
Limited Nutrient Access
Just as soil compaction stops water from reaching the roots of your lawn, it also prevents nutrients from passing through the soil. So, if you do not see any improvements after fertilizing your lawn, then it’s likely that the fertilizer is getting trapped above the roots. Again, lawn aeration is the perfect solution to overcome this problem.
Limited Nutrient Intake
For a lawn to absorb nutrients, a few conditions need to be met. For example, a healthy lawn will grow extensive root systems, including various types of roots. Some of these roots are more effective at absorbing nutrients than others. Your lawn needs vital elements like water, nutrients, and air exchange to achieve a healthy, established root system. So, if your lawn has a weak root network, it will limit the nutrient intake no matter how much food you provide. Lawn aeration will free up your soil and allow these elements to reach your lawn’s roots, improving your lawn’s ability to absorb nutrients and have healthy roots.
Restricted Air Exchange
Most people know that plants absorb carbon dioxide and release oxygen. While this is the process of the blades above ground, underground is a different story. Below the surface, your lawn’s roots are absorbing oxygen. This is called aerobic respiration. In other words, your lawn breathes underground. When the soil is compacted, the roots can’t breathe, preventing the breakdown of food molecules. When this happens, it limits your lawn from producing the energy it needs to grow, hence why lawn aeration is key to allowing air to reach the roots.
Poor Root Growth
Adding all these different issues together results in a lawn that isn’t happy. Not only will you see the top of your lawn struggle, but you’ll also begin to see the effects of struggling roots. The bottom line is that if the top of your lawn isn’t growing well, neither are the roots. So, getting out your lawn aerator will help provide your lawn with all the essential elements it needs, helping your lawn’s roots strengthen and grow.
Reduced Drainage
Finally, heavily compacted soil acts as a barrier and prevents or at least reduces the rate at which water can soak into the ground. Depending on your soil’s makeup, this can get really bad. For example, most of the continental US soil is clay. When clay soil is compacted, it can act like a pond liner and slows down water absorption. So, if you have an issue with standing water after it rains or after you have watered your yard, then soil compaction is likely the cause.
What to Do About Soil Compaction?
What is the solution to soil compaction? You guessed it–aeration. So what is aeration, and how can this reduce soil compaction? Let’s find out.
What is Lawn Aeration?
Lawn aeration is a method that reintroduces pathways or voids back into the soil to eliminate the effects of soil compaction. If you didn’t have a lawn in the way, then you could just use a tiller to turn over the soil. But this isn’t an option for lawns, not unless you want to restart your lawn every year… Me neither! So, instead of breaking up the entire surface of the soil, you can use an aerator to penetrate the soil with spikes or cores. Aerators work by puncturing the soil every few inches in a grid pattern. Various aerating tools are available to match different yards and physical needs.
What Tools Should You Use to Aerate a Lawn?
When deciding on the equipment for aerating your lawn, you first need to know how compact your soil has become. For example, you could use a spike aerator vs. a core aerator for a lightly compacted lawn, as spike aerators are less efficient. In other words, spike aerators create a smaller penetration, providing less aeration. The upside to spike aerators is that they typically take less effort to operate and are less aggressive on your lawn.
However, if your lawn is heavily compacted, you will want something a little stronger such as a core aerator. Core aerators remove a core of dirt about ½” across and greatly alleviate compaction. On the downside, these aerators are physically demanding to operate and take much more time to aerate a lawn than a spike aerator. But if you need a strong, effective aeration tool, then a core aerator is definitely going to be your best option. Alternatively, you can always opt for a towable version if you have a lawn tractor.
Examples of Lawn Aerators
I’ve put together a table to give you an idea of the different lawn aerators available and their cost. Personally, I use the towable versions as I have a large lawn and a lawn tractor on hand. But if your lawn is small to medium, then this is potentially going to be a little overkill. I’ll leave that decision up to you.
| TYPE | POWER | COST | TOOL EXAMPLE |
|---|---|---|---|
| Spike Aerator | Handheld | $30 | Colwelt Spike Lawn Aerator |
| Spike Aerator | Shoes | $36 | Leweio Lawn Aerator Shoes |
| Spike Aerator | Push | $54 | Colwelt Rolling Lawn Aerator |
| Spike Aerator | Towable | $169 | Agri-Fab Lawn Aerator |
| Core Aerator | Handheld | $40 | Hermsche Lawn Aerator |
| Core Aerator | Towable | $310 | Brinly Aerator |
What About Gas Powered Core Aerators?
One type of lawn aerator didn’t make the list: the gas-powered core aerator. Why didn’t I leave it out? These lawn aerators cost thousands of dollars and are not in the budget for most homeowners. But this doesn’t mean they are not available for you to use. With a quick trip to the Home Depot or Lowe’s tool hire department, you can rent a professional standard machine for about $80 a day. Visit the Home Depot’s Rental Department to rent a Classen core aerator.
When Should You Aerate a Lawn?
You should only aerate your lawn when it is actively growing to ensure it recovers quickly. Also, you should avoid aeration if your lawn is stressed or struggling with pests or diseases. This stress can make it harder for your lawn to recover.
How Often Should You Aerate a Lawn?
You should aim to aerate your lawn a couple of times a year. I aerate mine once in the spring and again once in the fall. As a best practice, I recommend aerating your lawn around the same time you dethatch.
What to Do Before Aerating a Lawn
One of the main things you’ll want to do before aerating your lawn is to ensure the soil is moist. You can do this by either giving your lawn a good soak a day or so before aerating or by aerating after it rains. Soaking the soil makes it easier for the spikes or cores to penetrate the ground. This is especially important if you are using a non-powered lawn aerator.
What to Do After Aerating a Lawn?
What to do after aerating is much the same as what you would do after dethatching your lawn. You should water, overseed as required, and fertilize your lawn using a quick-release fertilizer followed by a slow-release fertilizer. If you aerate and dethatch at the same time, then you’ll only need to have one aftercare process for both. That’s two birds with one stone.
How Do You Know if Your Lawn is Compacted?
You can do several tests to evaluate how compacted the soil is under your lawn. Some of these tests are very advanced, such as dynamic cone penetration tests (DCP), and are way beyond what a homeowner needs to undertake.
Compaction tests using tools such as an AgraTronix 08180 compaction tester allow you to perform quick tests around your lawn in different locations to ensure you aerate when needed and vary between spike and core as necessary. While these tools are not cheap, they should last for many years if they are used and looked after correctly.
If all these tests sound complicated and expensive, then you could just use a long screwdriver and poke it into the ground. If the screwdriver is hard to push into the ground, then this is an indication your soil is over-compacted. Now this isn’t a very scientific method or remotely accurate, but it’s a method many homeowners have been using for years with great success.
