Nothing is as satisfying as looking out your front window and seeing that beautiful centipede grass that frames your yard. But it doesn’t happen by accident or without effort. The value of watering and fertilizing are pretty much a given these days but one area that homeowners often disagree on is the need for core aeration.
Does Centipede Grass need to be aerated? Yes, Centipede grass requires aeration, but the frequency depends on the type of soil that you have. While all roots need oxygen, Centipede Grass doesn’t struggle with this as much because of its shallow growing roots. The more compacted your soil, however, the more aerating will benefit Centipede grass.
When it starts looking sparse or like it is dying, it can be stressful and confusing, especially if you are not familiar with the tendencies and risk factors of this type of grass. I am hoping to share my experience and some insights with you that will help reduce that stress.
What Aerating Does
Aerating is basically the process of penetrating the soil and removing sections, or “cores”, from the earth. This leaves shallow cavities throughout the lawn that makes it possible for oxygen and water to get down to the roots. It can also have the side benefit of allowing the roots to be able to reach deeper into the earth. This makes it possible for your centipede grass to be able to grow healthier and thicker.
The tale-tell sign that I noticed that first made me realize that I needed to begin aerating was brown patches that I noticed on my lawn. I initially thought I had some type of fungus growth; however, this was not the case. My second thought was thatch, which was also wrong. It turned out that the clay soil under my grass was tightly compacted and strangling the root system. This issue was compounded by a thick layer of thatch.
By aerating my lawn using a core aerator, I was able to really break up that thatch (not as effectively as dethatching, but it did make a difference) and was able to get to the root of my problems (pun intended). Tightly compacted clay is bad about not letting the water soak in. In fact, water will literally sit on top of the soil. Aerating allowed space for the soil to “breathe” as well as helping water get to the roots. It also allowed me to get an insecticide to the roots which were being ravaged by white grubs.
You may be wondering how the soil got so hard and compacted in the first place, and I wondered that too. Just walking and mowing over time is said to contribute to clay soil compaction but rain or watering the lawn can do it too. As the water goes into the soil it causes small particles to shift and this will compact it. Then it dries and it begins to crack like stone.
When you aerate the soil, it breaks up this compaction and allows it to sort of separate a bit more. It results in softer, looser soil that will take in water better and is easier for the roots to grow in. This is what I mean by allowing room for the soil to “breathe”.
In short, aerating can serve multiple purposes:
- Allows oxygen to circulate around the roots of your grass
- Allows water to more easily reach the roots of your grass
- Allows treatments like fertilizers and insecticides to reach the roots of your grass
- Breaks up thatch (though not as completely as a dethatcher)
- Loosens hard soil and makes it easier for your grass to spread its roots
If you really want a thicker, fuller centipede lawn, aerating is a great start.
Note: I have developed a five-step process for improving clay soil for lawns that includes aeration. Be sure to read this article so that you understand the benefits of a comprehensive clay soil improvement strategy if this is the type of lawn you are working with.
Holes Vs Cores
A buddy of mine had the idea of making this weird “aerating” contraption to pull behind his mower. It was basically a large metal pipe with metal spikes welded through it. The idea was that as he drove around mowing, it would be poking holes into the ground aerating the soil.
I want to explain why this is a horrible approach. It is based on the same flawed principle as those funny-looking spiked aerating shoes that used to be advertised on television.
By driving spikes into the ground to create holes, you are not relieving the compaction of the soil. If anything, you are compounding it by pressing the soil particles even tighter! Core aeration involves literally removing cores of dirt from the ground. This is what relieves compaction and it is a critical distinction. Don’t fall for spike aeration promises, please!
You have a few options when it comes to core aerators. First, you can rent a dedicate core aerator from local tractor supply stores or Home Depot. These run off of small engines like a tiller and work great because they are specifically designed for the purpose.
If you have riding lawn mower, I’m a big fan of pull-behind aerators like the Brinly PA-40BH (link to Amazon). It pulls plugs of soil as you pull it around behind your mower. It’s basically the outcome that my buddy was trying to create with his DIY project. Sometimes, quality costs less.
After using a core aerator, you will likely notice that your grass seems sparser. Don’t let this concern you. It is completely normal and is actually healthy for your lawn. This gives the centipede grass a chance to grow roots deeper into the soil so it can access more water and more nutrients vital to healthy growth.
Within a couple of weeks to a month, you will notice the holes filling in, as your grass pushes its roots deeper and grows healthier. You can increase the benefit by spreading nutrient-rich topsoil and letting it fill the holes.
Best Time to Aerate
For normal soils, core aeration is generally recommended as a spring or fall lawn care project. Clay soil benefits from two to three times per year I’ve found but your mileage may vary. It’s important to note that aerating too frequently can hurt your grass due to the damage caused to the rooting system. Let the condition of your lawn and common sense guide your judgment.
Once the risk of frost is over and your grass is coming alive, it’s time to aerate. You will be left with a bunch of small cores of dirt all over your lawn. If you have good soil you can probably leave it. Since I have clay, I always rake it up. I’m looking into investing in a pull-behind grass sweeper since I have two acres to deal with. If you have a small yard you can manage it with a rake and a little elbow grease.
Soil aeration should be done when the soil is moist. You can water it beforehand or wait for decent rain but don’t try it when the ground is saturated. This will allow for the best aeration while minimizing the damage to your lawn. I found that a couple of days after a good rain or watering my lawn worked best. I wanted to try to soften the ground without digging into thick mud.
How To Use A Core Aerator (Video Demonstration)
If you plan to rent an aerator, this YouTube video provides an excellent walkthrough of the basics of use for one of these. The host provides a lot of instruction as well as excellent suggestions on transporting, preparing, and using a core aerator.
Before you go out and rent an aerator, however, be sure to read Should You Rent Or Buy A Lawn Aerator? 5 Key Considerations
Breaking up a thick layer of thatch from aerating can really help to improve the condition of your lawn. A dedicated dethatching may be warranted depending on your situation but it’s surprising how much difference aeration alone can make.
It can look as if you’ve damaged your lawn after aerating when you see all of the holes and dirt cores everywhere, but it should fill in pretty quickly once the roots could get the water and nutrients they need. Decaying cores of quality soil can actually help to break down the thatch as well so if you aren’t fighting clay soil like me that may be yet another benefit.
It’s generally a good idea to follow core aerating with a slow-release nitrogen fertilizer. Before doing this, however, I recommend investing a small amount in a soil test.
Aerating is an excellent way to improve root growth and thickness of Centipede grass. The frequency should be determined by the type of soil you have and the condition of your grass.
It can also help to break up thatch though not as completely as a dedicated dethatching machine. You can find quality dethatching machines on Amazon. You may also be able to rent one locally.
But remember that aerating and dethatching are not the same. You want to use a core aerator to remove cores of dirt to allow oxygen, nutrients, insecticides, and water to filter better to the roots.
Finally, consider going over your lawn with a quality topdressing after aeration to allow the nutrient-rich mixture into the holes created by the aerator.
If you have clay soil that you are struggling to grow centipede grass on, be sure to review the five-step strategy for improving clay soil. It’s the same strategy that I am using to improve the health of the centipede grass that I have growing on the red clay soil in my yard.