Lawn aeration is defined by Biggs and Straton, as a perforation of the soil with small holes to allow air, water and nutrients to penetrate the grass roots.
Aeration essentially breaks up the layers of soil, and helps the roots grow much deeper and stronger, therefore creating a lawn free of weeds and turf which is very resilient.
Lawn aeration also encourages cohesive growth throughout the lawn by replenishing nutrients, oxygen and water to the roots and problem areas.
Why Should You Aerate Your Lawn?
There are several reasons why you may want to aerate your lawn, but the primary reason most people aerate their grass is to alleviate soil compaction.
The reason for this is that when your lawn soil is compact, your soil prevents the ability of air, nutrients and water from penetrating the soil and getting to the roots of your grass.
There are also other elements which need to be loosened, that are buried beneath the surface and when your lawn soil is compact, it can prevent air, water and nutrients from being absorbed.
The type of soil on your lot will dictate the need for aeration (for example dense soils that re heavy in clay may need more frequent aeration than loose, sandy soils). But the reality is that almost every lawn will benefit from regular aeration.
How to Know if Your Lawn Needs Aeration
Aeration isn’t necessary for everyone, but you should probably aerate your lawn for a few of the following reasons.
- If your lawn is used often, and you’d describe it as high traffic (for example, you might have pets or children running around on it every day which puts pressure on the soil).
- Another reason to aerate is if you recently put in your lawn. Often new lawns have a lot of pressure put on them, so it’s important to loosen the soil, get air to the roots, over-seed, and top-dress your lawn with organic compost. This will help your lawn get established and prevent weed growth.
- If your lawn seems to dry out or has a bouncy feel. This is another reason to aerate and it could mean you have a thatch problem. One way to check this is to remove part of the lawn with a shovel and dig four inches down. If your thatch layer is deeper than ½ an inch aeration is a good idea.
- Finally an important reason to aerate, is if you personally established your lawn by sod. Lawns that were grown from sod means there is soil layering. When there is a thinner soil over your other soil, this can create a drainage problem, and can stunt root development. Aerating and over-seeding your lawn will help correct this and improve your yard.
Best Ways to Aerate Your Lawn
If you have decided that you are going to aerate your lawn, it’s important to do it properly.
First make sure that the soil has enough water. It will be very difficult to aerate soil that is dry. Either try to aerate right after it has rained, or water your lawn the day before you begin.
There are plenty of aeration machines that only cover a small part of your lawn are once, so try to make multiple passes over the same area, and move the machine in different directions (i.e. East to West, then North to South).
If there are areas that do not need to be aerated, there is no reason to do so. Save your energy for the areas which need it the most.
In order to keep a cohesive lawn, you will want to allow any soil plugs that have been excavated, to dry and then break them up. You can break them up by running over the lawn and plugs with a lawn mower, but I use the back of a leaf rake once they’re dry.
After You Aerate Your Lawn
After this process, make sure to remember that your lawn continually needs care. Fertilization, mowing and regular watering is incredibly important to maintain your aerated lawn.
And as I’ve mentioned, right after you aerate is the best time to over-seed your lawn and amend the soil with a good organic compost.
Doing so will help the new seed and compost get down into the soil (in the holes) and you’ll see improved germination rates and improved benefit from amending the soil.
What is the Best Time to Aerate Your Lawn?
Just as the timing of when you plant new seed or water your lawn is important, the time of year you aerate your lawn is also important.
The best time to begin aeration is when the grass is able to grow and repair itself if any areas become open or destroyed when certain soil plugs are removed. This means you would want to aerate in the growing season (when that is for you, exactly, will depend upon your geographic location).
Cool season grass grows in the early spring and fall, while warm season grass grows in the late spring or early summer. Therefore, these are the best times to aerate for each type of grass.
If you work on your lawn during the wrong season, not only will you limit the benefit of the work you do, but you risk causing more problems that you had when you began.
Improving your lawn requires patience and planning.
How Often Should You Aerate Your Lawn?
How often you aerate your lawn depends mainly on which type of grass you have, your soil type and condition, and a visual assessment of how well your lawn is growing.
You should aerate whenever it seems necessary. This can mean when you have thatch, which is a layer of old clippings or other material that has developed on your lawn, or when you notice heavily-trafficked areas of your lawn struggling.
My rule of thumb is that aeration should be done every year or two (I have sandy soil on my lot, so I do it every other year), but if your lawn is in exceptionally good shape, you can probably do it less frequently.
What are The Different Ways to Aerate Lawns?
Aeration requires machinery, and there are three specific types of machines and tools used for lawn aeration. These are:
- Spike aeration,
- Slicing aeration, and
- Core/plug aerators.
The tool you use to execute any of these lawn aeration methods will vary depending upon your budget, and lot size.
There are both manual versions, walk-behind aerators, and tractor sized machines that you can tow with your lawn and garden tractor.
Spike Aerators for Your Lawn
Spike aerators put holes into the soil with an actual spike.
Some people use special aeration shoes that have spikes on the bottom to aerate their lawns. While cheap, these aren’t the best tool for the job. If possible, it is better to use actual spike aeration machinery.
Others just use a pitchfork or manure fork to push some holes into the ground. This can be a quick and easy way to aerate a section of your lawn that is particularly high-traffic. I will sometimes do this on areas near my front walkway where kids and visitors frequently take a shortcut across my lawn.
Slicing aerators usually have rotating blades. These cut through grass as well as thatch, and the blades cut deep into the soil to improve air flow and water penetration.
These are similar to spike aerators in that they do not take soil from the ground, but leave a space for water, air and nutrients to enter the soil. They also do not cause compaction of the soil.
Between spike aeration and slicing aeration, I prefer (and recommend) slicing aerators.
With that said, the best approach is…
Core Aeration for Lawns
The best method of lawn aeration is to use a core aerator (also known as a plug aerator). This is the method professionals use.
But most home centers and equipment rental services will rent you a professional core aerator which you can use on your own lawn to save money.
These aerators actually make rows with small spikes that remove the plugs of soil from the lawn. The aerator leaves these plugs on top of your lawn.
Not every machine is the same, and there are different variations of sizes with different widths and depths.
Which Method Should You Choose?
Aerators which remove plugs of soil are the most effective, according to most lawn care and turf experts.
This is definitely what I have found.
That said, the efficacy really depends on your lot’s type of soil. Also, consider the size of the lot you’re going to be aerating when choosing a tool and method for lawn aeration.
Poking methods like spike aerators can be less effective than plug aerators due to causing additional compaction around where you place the holes.
I recommend that you use an aeration tool that pulls soil plugs at least 2-3 inches deep. These should also be no larger than 1 inch in diameter and no farther than 4 inches apart for best results.
Lawn Maintenance After Aeration
There are a few types of maintenance that are very important to consider doing after aerating your lawn.
These methods of maintenance are fertilization, watering, and mowing properly.
Directly after aeration you can also add more seed (called over-seeding) while you fertilize your lawn. This is what I recommend, as it’s the best time to get the seed and fertilizer right down into the soil. You’ll get the most bang for your buck.
Aeration opens your lawn up to accepting nutrients. This will create a thicker and healthier lawn in general, along with the aeration, and instead of a chemical or organic fertilizer, I also recommend top-dressing with a thin (1/4″) layer of organic screened compost. This will keep the seed moist, and add valuable nutrients to the soil.
Whichever lawn aeration method you choose, you can either hire a professional or you can do it yourself.
If you have a large lot and your budget allows, hiring a landscaping company to aerate your lawn for you might be a good choice.
If you have a smaller lot and don’t mind putting some sweat equity into your lawn, rent an aerator and have fun! It’ll be incredibly satisfying.
As with any lawn maintenance routine, pay attention to what your lawn needs, and be proactive instead of reactive.
In the long run this will save you money and keep your lawn lush and beautiful.