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How Deep Does An Aerator Go?

Getting your lawn care done each year or two can feel impossible without the right equipment. For example, is it time to aerate, but you aren't sure how deep your tool will go? Is it better to create super deep holes in the soil, or are shallow ones better? Are all aerators the same?

Well, we've done some research, and here's what we found!

You can typically expect an aerator to go 1-6 inches deep and be 2-6 inches apart. Of course, the soil penetration depth will vary depending on the aerator you use. Some may have deeper, closer spikes, while others will be more spaced out and shallow.

Luckily, your aerator will benefit the ground if it pierces it a few inches, so aim for 2-3 inch spikes if you can.

As we start this article, we will cover all things aerating and discuss how deep one should go. Whether you haven't aerated before, recently bought an aerator, or have additional questions: we're here to help. With that said, let's dive right into this topic below!

Gardener Operating Soil Aeration Machine on Grass Lawn, How Deep Does An Aerator Go

How Deep Should An Aerator Go?

Using scarifier in the garden. The man fertilizes the soil in the garden, preparing for work on the garden. Aeration with a blue scarifier. The gardener works outside taking care of plants.

An aerator will generally penetrate the ground as much as six inches. However, your typical aerator may be closer to two or three inches deep, which seems to be the sweet spot for most gardeners.

As we said, the spikes on an aerator can be anywhere from one to six inches deep, being spaced apart by 2-6 inches. The design of an aerator will depend on how you use it, whether it's an attachment for your mower or simple spike shoes.

Regardless of design, you want to ensure the spikes on your aerator are deep enough to break up the soil. Since the primary goal of aerating is to create holes in the ground for water drainage, you shouldn't choose an aerator that only reaches one inch.

In addition, you also don't want your aerator to be too deep, as this can damage the soil and roots nearby. Try and find a happy medium.

How Big Should Spikes Be On An Aerator?

Depending on the ground you work on, your aerator's spikes may need to be around 4-6 inches. As we covered above, aerators come in a range of spike depths.

Your aerator should penetrate the soil, whether one inch, two inches, or deeper. The main priority is breaking up the compacted ground, allowing water, nutrients, oxygen, and fertilizer to move freely throughout.

If the spikes on an aerator aren't deep enough or have too much spacing between each one, that can cause poor-quality final soil. According to Timberline Landscaping, the best size for aerator spikes would be around four inches deep.

They claim that four inches are perfect for opening the ground, allowing water and fertilizer to penetrate deeper into the soil.

Of course, you'll need to ensure you don't have any irrigation lines running under the soil to use deeper spikes, or if you do, we suggest marking them.

Deeper spikes can become an issue for roots and water lines, as they are usually steel material.

How Big Should Aeration Holes Be?

Pile of plugs of soil removed from sports field. Waste of core aeration technique used in the upkeep of lawns and turf

Most times, you want to aim for aeration holes around 3 inches deep, 3 inches or less apart, and about 3/4 inches in diameter. Again, this is not the same for every garden, as some ground types are much more compacted and will require a deeper hole.

On top of that, you might also prefer slightly deeper aeration holes for your lawn. Some people like closer to six inches, so this comes down to the gardener.

Luckily, there are endless aerator products available, ranging in spike size, depth, and use. The best idea is to start with mid-sized spikes and see how the result is.

If the soil improves quality and drains better the next time you water/it rains, then stick to that spike. In contrast, if the soil in your yard doesn't improve after using a 2-3 inch spike, then go up a size.

Not all soil is the same, and it certainly won't respond the same way whenever you aerate it.

How Many Holes Do You Need To Aerate A Lawn?

When it comes to the number of holes an aerated lawn needs, this can be as many as 20 to 40 holes per square foot. Since aerating a property requires many small holes in the soil, you'll need to have quite a few per square foot to make a difference.

On top of that, if you use an aerating attachment for your mower or tractor, accomplishing the 20-40 holes per square foot becomes much easier.

Imagine walking through your entire property with spike shoes to do this. That would take hours and would end with sore feet and legs.

Furthermore, you can also find aerators you push, which are perfect if you don't own a tractor or mower. Try to make the aeration process as smooth and simple as possible: your legs, back, and feet will thank you.

You might even need to do a couple of passes through your lawn to accomplish better drainage and nutrient intake, so keep this in mind.

Agri-Fab Push Spike Aerator

This aerator has a walk-behind design, is 16 inches wide, has seven-inch spikes and five aerating wheels, has a steel weight tray, gives you 2-2.5 inches of aeration depth, and is easy to assemble.

View this product on Amazon.

How Many Passes Should I Make When Aerating?

Scarifying lawn with a scarifier. Person dethatching moss in a backyard, lawn maintenance, UK

When the time comes to aerate your lawn, start with one thorough pass. Ensure that you make enough holes in the soil to improve its quality.

Next, assess whether your lawn will benefit from a second or third round. As we mentioned, this is sometimes necessary depending on the soil compaction.

For example, you will likely need a few aeration passes with clay ground. That's because the consistency of clay soil is far thicker and more compact than that of a loamier mixture.

Over time, the ground can become tightly packed together. As this happens and worsens, your plants will have trouble growing correctly. That's when aeration becomes essential.

Therefore, one gardener may need one thorough pass with their aerator, while another might need to do two or even three in severe compaction.

Again, don't get too wild, as too many holes can counteract the positive deed you're attempting.

How Should I Prep The Ground Before Aerating?

Before you even touch your aerator, you need to do a few things to your soil. First, it is best to water the ground 1-2 days before aerating. This will ensure the soil is soft and ready to be broken up.

Many experts suggest using about one inch of water for your lawn, ensuring a smooth aeration process. Once that is done, you want to mow your lawn lower than usual at 1-1/2 inches and clean up leaves.

You will also mow one or two days before aerating, so this can happen the same day. Depending on how wet the ground is, you might prefer to mow first: do this in the order that makes sense for your lawn.

The goal is to get your lawn as prepared for aerating as possible. Remember, the ground will experience a bit of trauma immediately after the spikes puncture it, so take it easy before and after.

The last thing you want to do is put your lawn through extreme drought or soak it to the point of waterlogging right before aerating: moderation is key!

How Often Should You Aerate A Lawn?

spring scarifying the lawn using verticutter machine

Now that you know how to aerate the ground, how often should you do it? According to experts, high-traffic lawns require aeration every year. However, in lower-traffic areas, you might only need to aerate every 2-3 years for good results.

Since aeration can put the soil under stress right after it happens, you want to avoid overdoing it. For example, if you aerated less than 12 months ago and are thinking of aerating: don't.

Doing this too frequently can have a reverse effect, causing the ground to become unlivable for your grass and other plants. Too many holes in the ground can deplete it of nutrients, oxygen, and proper drainage, so once every 12-24 months is ideal.

Furthermore, if your lawn has soft, loamy dirt, you may be able to hold off even longer than two or three years. Again, this comes down to the property and traffic.

What Happens If I Don't Aerate My Lawn?

If you choose not to aerate your lawn, expect it to be less successful and vibrant. Generally, when you don't aerate a property for many years, the grass struggles to grow, often thinning and losing its color.

On top of that, you might notice the soil in your lawn having trouble moving water. For example, let's say it rains hard for a few days. A lawn with little to no aeration won't process the influx of moisture well, often filling with pools of stagnant water.

That sitting water can cause your grass to drown, inviting fungus to the area. So, for the sake of your grass's health and color, we recommend once-yearly aeration.

To Wrap Up

Woman scarifying a garden lawn with a scarifier. Scarification of turf, a spring garden maintenance job

Whether you need to aerate your lawn or haven't thought of this before, it's essential to use the right spikes. We found that you should aim for 2-3 inches of aeration depth in your yard, although some people prefer a deeper 4-6 inches.

Since aerators come in various sizes and depths, you can typically find the perfect one wherever you go. However, we recommend starting with a 2-3 inch penetration and moving up if the soil doesn't respond well.

Even though aeration can be beneficial, too much depth or frequency can cause trouble in your lawn.

And while we have your attention, check out these helpful related garden posts below!

Can You Aerate Your Lawn In The Spring? Should You?

How To Aerate A Lawn With Spike Shoes

What's The Best Time To Aerate And Overseed A Lawn?