For years I didn’t believe that I needed to aerate my lawn. Honestly, I thought it was just a gimmick. There’s a lot of snake oil being sold as magic solutions to compacted soil and it can be hard to figure out what’s real and what’s not. So let’s just settle this once and for all.
Does lawn aeration really work? Lawn aeration is an essential and highly effective method for improving compacted soil. However, it should be considered part of a comprehensive soil improvement strategy, not a one-and-done solution.
I have been testing the effectiveness of lawn aeration on a section of my yard for the past three years, intentionally treating only a designated area. We’ll look at the side-by-side results of this testing and some little tweaks that I’m using to maximize my results.
What Is Lawn Aeration?
In simple terms, lawn aeration is the process of loosening compaction of soil under a lawn to improve root growth, water drainage, and fertilization uptake of turf. It also helps oxygen to reach the root structure of plants and grass.
This air exchange is essential to healthy, vibrant growth (source).
There are different approaches to lawn aeration depending on the type of soil, the level of compaction, and the specific turfgrass. Let’s dig into this a little just so that you have the basics.
Heavily compacted soil is best treated using core aeration. This process involves a machine that uses specially designed prongs (often called “spoons”) that plunge into the soil and pull up cores of the soil.
Lawns with special turf grasses such as golf courts often use a spike aeration technique. This approach uses large metal spikes that are pushed deep into the soil.
The benefit of spike aeration is that it does very little damage to the appearance of the lawn. The downside, however, is that spike aeration is not nearly as effective as core aeration.
In fact, if you have a heavily compacted soil like clay, spike aeration can actually result in even more compaction (source).
There is one other approach to aeration that deserves mentioning here and that is liquid aeration. While I don’t like the term (I prefer to think of it as liquid soil conditioner) I understand why it’s called aeration.
There are people who sing it’s praises and those who swear it’s nonsense, but I have come to realize there is a real, tangible benefit to applying a liquid soil conditioner, especially when doing it prior to core aeration as it helps to soften the soil and allows the spoons to dig in and pull out solid cores.
For more information, read Does Liquid Soil Conditioner Work? The Easy Aeration Promise.
Is Lawn Aeration Worth It?
Lawn aeration is beneficial to almost any soil but it offers the most benefit for soils that are heavily compacted. Clay soil, for example, has very small pores and does not allow air exchange.
It also restricts the growth of roots and encourages microbacterial activity that is present in healthy soils (source).
If grassroots cannot grow deep, the turf will be less hearty. This can result in grass that is highly susceptible to drought.
If you have Centipede or St. Augustine grass, we have more info on drought tolerance here:
The point is this: lawn aeration is intended to break up the compaction of soil, allowing for deeper root growth, healthier grass, and better water absorption.
Remember, healthy soil means a healthy, thriving lawn.
When my wife and I built our house, I was faced with growing grass on some of the most challenging red clay soil that you’ve ever seen.
I had a local dirt company prep the ground with what we call topsoil around here but it’s not a nutrient-rich material. It’s just dirt and that’s better than seeding straight into the clay.
I sodded close to the house but with over two acres there was no way I was going to be able to do the whole yard. And so, I seeded. That’s my shop in the background and the yard in front of it was one of the areas that I seeded.
And so, I seeded, watered, fertilized, and did everything I was supposed to. But because I’m always testing I chose to divide this particular area for a comparison between aerating and not.
Roughly one side has been aerated and treated with a five-step approach that I’ve used to improve my clay soil. The other side has been watered and cared for but it didn’t get the aeration.
Here’s a couple of close up pictures so that you can really see the difference in how the grass has spread and thickened in the aerated section compared to the non-aerated area.
Pictures hardly do this justice, but the grass in the aerated section is much thicker and denser. It has filled in the bare areas fully and has a nice cusion-like give under your feet. The non-aerated area remains hard and still has a lot of bare spots where the grass just hasn’t taken hold.
Here’s another way to really compare. I sat a 5-pound weight onto the ground on both the non-aerated side and the area that has received regular lawn aeration. What I really want you to see here is the difference in how “deep” the weight appears to sink into the ground in the aerated area.
Now, there are actually two important considerations at play here. First, the grass is deeper and thicker so the weight appears to sink deeper. But the second part is the “give” of the turf underneath the weight. It really does sink a little. It’s that soft comfortable barefoot feeling that people like about a nice thick lawn.
Keep in mind that the areas I’m comparing here are only about 5 or 6 feet apart. It’s not a different type of soil, it wasn’t seeded using an alternative method or at a different time. The only difference between these two areas is in how the soil was aerated over the three year period.
And so, from my experience, there is absolutely no argument against the effectiveness of core aeration. I am a bit of a fanatic and so I do a lot of testing in my yard and try a lot of unorthodox approaches. If something doesn’t work, I call it out. But lawn aeration makes a difference, plain and simple.
Best Way To Aerate A Lawn
Depending on the size of your lawn and your budget, you have about four realistic options for getting this job done.
For a very small yard, you could do this manually with a core aerator hand tool (link to Amazon). These tools are effective because they are not just spike aerators… they actually pull cores from the soil. But its really intended for confined spaces. If your yard is really small, this is the most economic approach.
For larger yards, it comes down to cost, convenience, and long-term planning. You can rent a dedicated core aeration machine at a local hardware store, buy a pull-behind aerator that hooks up to your riding mower, or just pay a professional landscaper to do it for you.
I’ve outlined the criteria you need to use on making this choice in Should You Rent Or Buy A Lawn Aerator? 5 Key Considerations so be sure to read that article if you are trying to decide which way to go.
For now, just know that the best approach really depends on your situation. The only rule of thumb that I’d really impress upon you here is that core aeration beats spike aeration in almost any situation (unless you are running a golf course and need to keep the turf super-smooth at all times).
Can I Mow Right After Aerating?
Mowing your lawn immediately after aerating offers the benefit of mixing nitrogen-rich grass clippings into the aeration holes. This can help to improve the overall quality of the soil.
If you are overseeding your lawn after aerating, however, it may be best to wait. The air movement of the blades will likely blow your seeds away. So keep that in mind. Personally, I believe that mowing right after aerating has real value. The more organic material we can actually get down into the soil, the better the quality of soil will be in the long term.
Does Aeration Kill Weeds On A Lawn?
This is a common question and the answer can be a little deceiving. You see, lawn aeration itself does not kill weeds but it does encourage deeper root growth of grass. By creating an environment where the grass can thrive, it allows it to grow thicker and more effectively choke out weeds.
So it’s a little shady to say that aerating your lawn will kill weeds. But you can certainly grow a thicker, healthier grass turf which will discourage weeds from proliferating throughout your yard.
I’ve given it enough time to say conclusively with quite a bit of confidence that aeration makes a noticeable and measurable difference in the quality of a lawn. It won’t improve your grass overnight but with time and consistency, it really can make a difference.
Just remember that core aeration alone is not the end-all-be-all of nurturing a thriving lawn. You need to water it, give it the nutrients that it needs, and treat any fungus or pests that endanger it.
Ultimately, lawn aeration is just one part of a comprehensive lawn care solution. It shouldn’t be overlooked but it should also not be relied on as your sole approach.
If you have a larger yard and riding mower or ATV, be sure to see my review of the Best Pull Behind Aerators: Key Features Compared.