Dethatching Lawns: What, When, and How

Maintaining a beautiful and picture-perfect lawn is not an easy task. There are many potential problems you might encounter even though you’re meticulous about weeding, seeding, mowing, and watering your lawn. These problems include discoloration, thinning, weeds, insects, molds, brown patches, thatch that makes your lawn lackluster in color and health.

However, don’t eagerly blame yourself and your efforts when this happens. Sometimes the cause of an almost lifeless lawn is thatch. Unfortunately, plenty of homeowners don’t know that their lawn is infected with the hidden enemy. Nevertheless, you don’t need to fret since we are here to educate you on the problem and possible solutions to combat the thatch. 

What is Thatch?

Thatch is a compact layer of organic material that covers the surface of the soil. Moreover, it is the unwanted layers of dead grass that may be exposed when lawns are mowed. Thatch is the growth of excess, dead organic matter at the base of turf stems.

Most lawn grasses grow much faster than they die, so this matter builds over time to form a layer just below the soil surface. This layer can be composed of old remains of roots, stems and leaves, and insects, including termites and ants forming their nests in there.

A thin layer of thatch, about ½ an inch thick, is beneficial to your lawn health. It serves as an organic mulch that helps to protect against significant fluctuations in soil temperatures and conserves soil moisture. Moreover, it allows the nutrients, water, and air to penetrate the soil and grassroots. However, when the thatch layer becomes one inch or more, it becomes a problem.

What Is Thatch

A thick thatch layer can turn into a perfect breeding ground for insects, fungi, bacteria, and weed seeds to grow in. Moreover, it blocks the fertilizer, water, and air from reaching the grassroots. In addition, the grassroots get trapped, resulting in them being vulnerable to drought, heat, stress, and eventually dying. Thus, you would have patches or continuous lines of a dead spot in your lawns.

When to Dethatch Your Lawn?

The first visible sign of thatch is when the lawn has become uneven. When this happens, go and check your lawn’s thatch layer by digging up a tiny wedge of your lawn grass and soil using a garden trowel or spade. You can then easily see and measure its thatch layer.

If the layer measures one inch or more, it’s the cause of poor grass color and the grass’s weak, thin growth.

After confirming that the thatch does more harm than good, it is time for dethatching. Remember that when you dethatch your lawn, it should coincide with the peak growth period of your grass type. That is because active grass growth aids in your lawn’s rehabilitation.

It is best to dethatch cool-season grasses in late summer or early fall. On the other hand, the ideal time to dethatch warm-season grasses is after spring green-up, as they enter early summer’s peak growth. However, never dethatch your lawn when it is stressed or dormant since you can damage it beyond repair.

How to Dethatch Your Lawn?

Dethatching is the process of removing the thatch in your lawn using a dethatching machine or doing it by hand. There are multiple methods on how to dethatch your lawn available nowadays.

Below are two of the most popular methods you can use in dethatching your lawn:

Dethatching Rakes

Dethatching rakes are short-tined rakes that are sharp and thin designed to dig into your lawn and pull out the thatch that builds up. This equipment is most suitable for removing and maintaining light thatch on small lawns or part of a lawn. Moreover, you can use a standard bow rake if you have a little thatch.

In addition, if you also want to multitask dethatching your lawn and having an upper-body workout, then dethatching rake is perfect for you.

Dethatching Machines

How to Dethatch Your Lawn

The dethatching machine can either be powered by gasoline or electricity that resembles a push lawnmower. There are two (2) types of dethatching machines: scarifier and power rakes.

Scarifiers are gasoline-powered machines with a series of thin metal blades mounted vertically on a spinning horizontal shaft. The blades are designed to cut the thatch layer as well as the topsoil. As a result, the cut thatch is brought to the surface, resembling a grass clipping where you easily gather and remove it. This machine is best suitable for dethatching deep and dense thatch.

However, you need to proceed with caution because this is an aggressive method of dethatching. In addition, it is not suitable for lawns that are not in good health.

A power rake is a series of spring-loaded tines on a bar. It is moved around the lawn using a machine such as a mower. The tines are designed to dig deep enough to tear out the thatch as the machine moves over the lawn. Power rakes are best for taking out thinner thatch layers and are commonly used by landscapers. This approach is less traumatic for your lawn, but it is still as effective.

The Bottom Line

There are several methods and solutions that you can do to dethatch your lawn. What you use will all depend on your lawn, the severity of the problem, and your personal preference. Moreover, you can always ask a professional, especially if you have over two-inch thick thatch in your lawn. Research and educate yourself because it’s better to be safe than to damage your lawn beyond repair.


Author: Matt Hagens

Hi, I’m Matt the owner of Obsessed Lawn. I love to be outside working on my lawn, planning my next project. I created this website to help people like you find the best products for yard care and great advice. Learn more about me and find me on Facebook.