A picture of a lawn mower on grass with text that reads how to properly dethatch a lawn with a mower attachment.

How to Properly Dethatch a Lawn With a Mower Attachment

A green, luscious lawn is the prize of any home or business. Every day, people spend time clipping their grass, setting a timer on the watering system, and spreading fertilizer. Lawns are the foundation for any beautiful landscape.

There is a little known fact about growing grass that involves something called thatch. Thatch is a hidden component that can create eye-catching green grass. But, too much of a good thing could cause problems. 

In this article, we are discussing what thatch is and why it’s essential, the process of dethatching, and how to dethatch a lawn with a mower attachment. 

What is Thatch?

Thatch is a layer of organic material found where grass stems meet the roots. It consists of crowns, roots, stem nodes, and vascular tissues. In the right amounts, it’s very beneficial to grass growth. 

The breaking down of organic material creates an environment readily able to take in nutrients and water. When thatch is at the right levels, it is loose and provides protection and nutrients to the soil.

Thatch heats up and dries out quickly. It can also lead to mower scalping. 

Grass clippings left on the lawn after mowing do not create thatch. It occurs naturally over time. All yards have a thatch layer, but certain grasses like Kentucky Bluegrass or Bermuda grass are more prone to thatch buildup

What Does Thatch Look Like on a Lawn?

When you look at your lawn, you probably won’t see thatch. The best way to know how much thatch you have is by doing a little digging. 

Choose an inconspicuous area to dig up a small portion of your lawn. You will be analyzing the spongy brown area just beneath the surface of the soil. 

A healthy layer of thatch will be no more than half an inch thick. If your layer is one inch or more, your lawn will suffer. 

Do You Really Need to Dethatch Your Lawn?

A picture of a well maintained green yard.

Dethatching your lawn is a personal choice. One that could give you the yard you’ve always wanted. 

Dethatching a lawn is the process of thinning the thatch layer. It allows nutrients and water to reach the grass’s roots. Dethatching also helps keep those pesky weeds at bay by promoting more grass growth. 

If you choose not to dethatch, your lawn can begin to turn brown. The grass will not get the nutrients it needs to grow because the layer of thatch will begin to act as a barrier. 

This barrier will create an environment for fungus and mold to grow. It will also suffocate the roots because air is unable to enter and travel through the soil. 

For more information about why you should consider dethatching your lawn, check out this article from the University of Washington. 

Can Dethatching Hurt Your Lawn?

Dethatching can hurt your lawn if it is not done correctly or at the right time. The first thing is to determine if your lawn truly needs dethatching. Deciding this is done by either taking a lawn sample or consulting with a professional lawn care expert. 

Dethatching your lawn in the spring is not recommended. Often, springtime is when people are anxious to get outside and begin preparations for a beautiful landscape. The problem is that there are parts of your lawn that may still be dormant from the winter. 

If you dethatch in the spring, you can rip up dormant grass or hurt grass already beginning to wake from their winter nap. Grass could become injured and unable to recover from the process of dethatching. You could also awaken noxious weeds you were trying to avoid. 

So when should you dethatch your lawn? To avoid hurting your lawn, dethatch in the fall and only if needed. 

Is Dethatching the Same as Aerating?

Most people know about aerating. It is common to aerate your lawn each year after the threat of frost. Aerating your lawn is beneficial, but it is not the same as dethatching. 

The process of aerating will leave small holes in your soil. Those holes allow for air, water, and essential nutrients to enter and flow through the soil. To aerate your lawn, you will use a special implement that is either pushed over your lawn or pulled behind your riding mower. 

Dethatching your lawn is similar to aerating, but the difference lies in what dethatching removes from the soil. A thick layer of thatch can suffocate the grass’s roots, so the process of dethatching thins out the thatch layer. 

You can water, fertilize, and seed your lawn after aerating and dethatching. Just remember that if you have a thatch problem, aerating will not fix it. You must dethatch. 

How to Use Mower Blades to Dethatch Your Lawn

We have established what thatch is and how it affects lawns across the world. Now, let’s look at how to dethatch. Specifically, by using a mower blade.

Do Mower Dethatching Blades Really Work?

The simple answer is yes. Dethatching mower blades can be very efficient at getting the job done. Our advice is to choose wisely before making a purchase. 

You can purchase blades that have nylon tines or metal ones. There are attachments for mowers, or you can purchase a machine designed just for dethatching lawns.

With the variety of dethatching blades on the market, you have many workable options to get your job completed efficiently. 

How to Dethatch With a Push Mower

Dethatching your lawn with a push mower is pretty simple. There is some work involved by changing the blades, but the result can give you a lawn the entire neighborhood will want. 

Follow these steps, and you will be dethatching like a pro. 

  1. You will need to purchase dethatching blades for a walk-behind mower. Be sure to purchase a blade that fits the deck width of your mower.
  2. Remove the existing blade from your mower.
  3. Install the dethatching blade onto your push mower.
  4. Turn on the mower and begin making passes across your lawn.
Arnold 490-100-005621-Inch Deluxe Universal Detaching Blade for Walk-Behind Mowers
  • Replacement deluxe dethatching blade
  • Fits MOST (Not all) walk-behind mowers with a 21" and 22" deck cutting width
  • For AYP/EHP/Sears/Craftsman, Bolens, Honda, Huskee, Husqvarna, Lawn-Boy, MTD, Murray, Poulan, Snapper, Toro, Troy-Bilt, Yard Machines and Yard-Man

When using a push mower, you have the option of using a bagger or not. If you do not have a bagger, you’ll need to rake up and discard the thatch from your lawn. Don’t leave this lying on top of your lawn because it will kill the grass, and it typically looks unsightly. 

How to Dethatch Using a Riding Lawn Mower

Using a riding lawn mower can make dethatching a large yard much more comfortable and quicker. The process is similar to using a push mower, with the only difference being the blade attachment. 

Riding mowers come with a hitch to attach various implements too. For dethatching, all you need is to secure a dethatching tool to the hitch and pull behind the mower. 

Agri-Fab 40-Inch Tine Tow Dethatcher 45-0294,Black
  • Tine de-thatcher uproots dead, matted grass and dislodges hard-packed dirt for planting
  • Twenty Durable spring tines for easy thatch removal; Penetrates and turns up dried grass, weeds, and soil in 40-inch wide swathes
  • Rust-proof and replaceable spring-loaded tines are heat-treated for greater durability

Step-by-step instructions are as follows.

  1. Mow your lawn to a maximum height of 3 inches. Dethatching is most beneficial when lawns are cut short.
  2. Park your mower on a level spot and turn off the ignition. Using the hitch mount arms of the dethatcher, roll the implement toward the mower. While holding the bolt at the top of the hitch mount, turn the nut located underneath and pull the bolt out. 
  3. Place the hitch mount arms above the mower hitch. Insert the bolt and screw the nut back on. 
  4. Lower the dethatcher toward the mower by the lift handle on top of the dethatching implement. Check that the front and back tines are touching the ground. If not, make adjustments by loosening rear and forward hex nuts and carriage bolts. 
  5. Start your mower and begin dethatching. You may need to go over your yard a couple of times, catching the same spots more than once. The best way to accomplish this is to work in a cross-section pattern. 

If you don’t want to pull your dethatching tool behind the mower, you have the option of purchasing a dethatching blade. In this situation, you will have to take the time to remove the mower blades and place the dethatching blades on your mower. 

What Should You Do After Dethatching Your Lawn?

After you have spent the time to dethatch your yard, it is crucial to complete a few more steps.

The process of dethatching is hard on a lawn. You are basically tearing up parts of the soil. While it is a good thing, it can leave your yard vulnerable to the elements. 

The first thing to do after dethatching is to rake and gather thatch on top of the ground. Never leave it lying on top of your grass. If you have not used chemical fertilizers too freely, you can use thatch as compost or mulch. 

To avoid other potential problems, make sure to place the sprinklers out once you have finished. 

A thorough watering can help the soil and existing grass recover from the stress of dethatching. Watering will keep the soil temperature stable, and all the grass stems hydrated. 

Another tip is to spread fertilizer across your lawn. Dethatching will leave the soil loose, making it much easier for nutrients from fertilizers to reach the roots. If you are using chemical fertilizer, be careful not to over-fertilize. Too much fertilizer is a primary reason for the overgrowth of thatch. 

Look for any bare spots in your lawn. After you dethatch is the best time to seed your lawn. You can overseed the existing lawn while paying particular attention to those unsightly bare spots. 

Don’t expect to see results immediately. It takes an average of three or four weeks to see the product of all your hard work. 

A picture of a well manicured lawn and another picture of a mower going through the lawn. Text in-between the pictures reads how to properly detchatch a lawn with a mower attachment.

Let’s Review

We have given you a lot of information, so let’s review for a moment. Dethatching is an integral part of lawn care. Don’t dethatch your lawn unless it truly needs it. Too much dethatching could damage your lawn.

When dethatching your lawn, be sure to mow the grass to a shorter than standard length. Most experts say to cut your grass to a height of three inches or less. 

You can use a push or riding lawn mower to dethatch your lawn. Just follow the instructions listed above, and you will be on your way to a beautiful yard. 

Put the final touches on your lawn by watering, seeding, and proper fertilization after dethatching is complete.

Dethatching is only one step to having the lawn you desire. It does require work but will extend the life of your yard. Along with preventative care, learning how to dethatch a lawn with a mower attachment will give you a beautiful foundation for a stunning landscape.