Dethatching Your Lawn: Why, When, & How To Start

Dethatching your grass is one of the best ways to get the best looking lawn on your block.

But, if not done correctly, dethatching can actually wreak havoc on your grass.

In this Ultimate Beginner's Guide To Dethatching Your Lawn, you'll learn all about dethatching: what is is, why you should do it, how you should do it, and common pitfalls to avoid. 

Read on to understand everything you need to know about dethatching your lawn. 

What Is Lawn Dethatching?

When you dethatch your lawn, you're basically removing anything between your grass and the soil surface that can prevent your lawn from growing—things like grass clippings, twigs, debris, pine needles, and dead grass leaves.

This process is usually done either by hand, with a special type of rake, or with a lawn dethaching machine (more on this below).

A picture of lawn thatch

Lawn thatch is an organic layer of grass stems, grass clippings, or mulched leaves that have not had the chance to decompose yet. Thatch sits between the grass blades on your lawn, and the grass roots and soil below. If you have a thick layer, you'll want to remove any loose thatch.

While thatch can have its benefits, if you allow too much of it to accumulate in your lawn, it can cause serious issues for the health of your grass.

Reasons You Should Dethatch Your Lawn

Do you really need to dethatch your lawn? Here are some reasons why you should.

  • It can increase the amount of water and fertilization. The dethatching process allows air, water, and fertilizer to penetrate the soil more easily, promoting healthy lawn growth, which in turns makes your grass look that much better.

  • It can make your grass "stand" up straight. We all want a lawn where the grass is sticking straight up. Not only does it look cool, but it makes for better cuts as well. When you dethatch your lawn, it helps to get the grass to stand up straight.

  • It gets rid of all the "crap" in your yard. Besides the "health" benefits that dethatching provides, it also makes your lawn cleaner, simply by removing any twigs, debris, and pine needles that are in the way. All of that junk makes for an ugly-looking lawn.

Note: You should only dethatch your lawn when it's necessary. If you dethatch too early (a thatch layer of less than 1 inch), you can actually cause damage to your lawn. This is because the aggressive raking involved in thatching can rip up grass roots and make your lawn susceptible to disease and pests. Be sure to read our guide on the pros & cons of dethatching your lawn to get the full picture.

When You Know It's Time To Dethatch

But how do you know when you should dethatch your lawn?

Here's a general rule of thumb to follow:

If a thatch layer greater than 1 inch is present, then you should dethatch your lawn.

If you have a thin layer of thatch—less than 1 inch—that can actually be beneficial for your lawn, since it reduces soil compaction. In that case, you don't have to do anything.

Looking for thatch

But when the thatch layer grows thicker than 1 inch, that's when it starts to prevent air, water, nutrients, and all that good stuff from reaching your solid. Which is a problem!

And that's when you know it's time to dethatch.

One tip before dethatching: mow your lawn to two inches, as this will produce the best results when removing excess thatch.

How To Dethatch Your Lawn

(3 Different Methods)

Method #1: Rent a lawn dethatching machine

Back in the day, before engineering feats allowed you to own your own dethatcher, it was common to rent a dethatcher for the day to dethatch your lawn.

And while renting a dethatcher is still an option today, we definitely don't recommend it.

For starters, it's expensive. I'm researching one on Lowes.com right now and the rental for 24 hours is $75! You can buy your own dethatcher (more on this below) for just a little bit more than that! So in terms of value/cost, it's a bad deal.

You don't want to be pushing this thing around all day

Number two, these rentals are huge. The one from Lowes weighs 147 pounds! Good luck pushing that thing around your lawn all day when it's 80 degrees outside.

Number three, it's inconvenient. You have to pick up and return the dethatcher to the store. Who has time for that?

So, yeah: don't rent a dethatcher, or a verticutter, or a scarifier, or a power rake for that matter. 

Method #2: Use a dethatching rake

A much better option is to use a dethatching rake, like the Groundskeeper II.

This lightweight rake (it weighs just two pounds) is ultra-sturdy and works MUCH better than a regular rake when it comes to dethatching.

It really gets in and hooks onto all the twigs, debris, and ticks in your yard, without much downward pressure required on your end. The tines do a great job of cutting through the grass and really grabbing all the stuff you want to remove.

Now, while a dethatching rake is an excellent way to manually remove thatch ... it's still very much a manual process, and really only works with a thinner thatch layer.

So, we really only recommend using a rake if you have a smaller yard. Because if you tried detaching a LARGE yard with this rake, you're going to get REALLY tired. 

Method #3: Use an electric dethatching machine

By far the best option for dethatching your lawn is to use an electric dethatcher, like the Greenworks 10. It operates much like a lawn mower does.

This nifty little machine provides the best of both worlds when dethatching:

It's nearly as big of a workhorse as the bigger, heavier machines you can rent from Loews and Home Depot ...

... and it's just as effortless of using a dethatching rake, while only being moderately more expensive. And, it won't tire you out on larger yards!

Basically, it hits the sweet spot: you can dethatch larger yards quickly, without breaking the bank (or your back), and it's quite easy to use.

It's easy to assemble, lightweight, a great bang for your buck, and works on large yards. The only thing to be aware of is you're going to need a heavy duty extension cord to operate it.

When To Dethatch Your Lawn (Seasons)

Thatch

So, when should you dethatch your lawn?

The best time to dethatch is when the lawn is growing most actively.

This is going to depend on the type of grass that you have!

For cool-season grasses (Kentucky bluegrass, perennial ryegrass, fine fescue, tall fescue) that's usually going to be either early spring or early fall.

For warm-season grasses (bahia grass, bermuda grass, centipede grass, St. Augustine grass, and zoysia grass), that's typically end-of-spring through the beginning of summer.

Note: you should avoid dethatching in late fall or winter, as that will leave your grass damaged and weak, which can affect its ability to survive. 

Generally speaking, you may need to dethatch once per year.

What To Do After Dethatching

So, what should you do after you're done dethatching?

Well, you definitely want to rake up the thatch.

Then, you could just do nothing, and be done with it.

But if you're interested in establishing a solid lawn care routine, we recommend the following:

Rake up the thatch

After you dethatch, your lawn is going to look kind of ugly!

First, you'll want to rake up all that thatch that's now sitting on top of your grass. You can either compost it, or throw it away.

Either way, you'll want to clean it up, not only because it's an eyesore, but also because it won't break down naturally just sitting there.

Core aeration

It's best to perform core aeration immediately after dethatching your lawn.

Aeration is basically poking holes in your soil to all it to breathe, while gettring all that good water and nutrients into the soil.

This is how we help the roots grow stronger, which gets us that nice, luscious lawn we all love.

Overseeding

Overseeding

Next, you should overseed your lawn.

Overseeding is simply planting grass seeds right into the turf, without digging up the soil.

The reason we do this after dethatching is because we want to cover up any bare spots that were left because of the dethatching process.

Apply fertilizer

Next, you should apply some fertilizer.

Fertilizer works together with your soil to supply all of the nutrients that your grass needs during the growing season to keep it looking healthy and help it grow.

Preventing A Thatch Problem

Of course, the best way to "treat" a thatch problem is not having one in the first place!

But how do we do that?

Let's go back to basics. Remember, thatch is basically when "new" grass grows faster than "older" grass can break down. 

So once way to slow down a thatch problem is to keep your grass from growing too quickly. (Yes, there is such a thing!)

When it comes to turbo-charging your grass, that means you should be mindful of giving it too much water, and hitting it with too much fertilizer.

That's one part of it.

The other part is regular upkeep after mowing. You know, raking your leaves consistently and getting rid of some of the grass clippings—as these things cause the layer of material on the lawn surface to thicken.

Dethatching vs. Core Aeration

You might be wondering: is dethatching the same as aeration?

If you do one, must you do the other?

Let's break it down:

Dethatching

As you know, dethatching basically involves raking your lawn aggressively to remove any junk that's preventing water and fertilizer to get into your grassroots. If your lawn has a thick thatch layer, then dethatching has lots of benefits, as we've discussed.

However, you have to be careful with dethatching. If you do it unnecessarily, you can badly damage sensitive grassroots. So, it's a bit of a judgement call.

Core aeration

aeration

Aerated grass

Core aeration, on the other hand, is almost always a good thing.

Again, with aeration, we're basically punching a bunch of holes in the grass so that air, water, and nutrients can penetrate deep into the soil. This process is especially beneficial is your lawn is badly compacted.

You should aerate your lawn regardless every few years.

Frequently Asked Questions

Can You Dethatch With A Lawn Mower?

Technically, you can dethatch your lawn with a dethatching blade mower attachment. However, it's not the best tool for the job and we don't recommend doing so.

Can I Use A Regular Rake To Dethatch?

Yes, you can use a regular rake to dethatch your lawn. Granted, using a regular rake won't produce a result nearly as good as using a dethatching rake, or a dethatching machine. In fact, speaking bluntly, it's a complete waste of time and effort. Don't do it.

How Much Does It Cost To Dethatch A Lawn?

If you're looking to pay a landscaping company to dethatch your lawn for you, you can expect to pay on average about $200 per hour. Obviously, this is going to depend on which company you use, which part of the country you're located in, and some other factors as well.

Is It Better To Dethatch When The Soil Is Wet Or Dry?

For best results, dethatch when the soil is moist. You want to avoid dethatching when the soil is very wet or very dry. If you do it when it's too wet, you're going to risk pulling out the roots.

Does Dethatching Help Drainage?

Yes, one of the big benefits of dethatching is that by removing the thatch layer, it will improve the drainage of the soil.

Why Does My Lawn Look Bad After Dethatching?

If your lawn still looks bad after dethatching, it could be any number of reasons. You may need to clean up the thatch more thoroughly, or hit it with some fertilizer to help patch up any dead spots.