Do you want to know how to thin grass that is too thick? Maybe you aren’t sure how to tell your grass is too thick, or what makes grass be considered too thick vs a healthy thickness?
The thickness of grass being considered unhealthy depends on the thatch that your grass produces. While not all grass types create thatch, most thick ones do, and if not taken care of properly, can slow growth, cause diseases to spread, and create dead patches on your lawn.
But don’t worry, we are here to help. Keep reading to learn more about thinning grass, as well as the tools you can use, and some common questions you may have about your lawn.
Can Grass Be Too Thick?
Yes, grass can be too thick. Having thick grass can lead to a lot of problems, including too wet of a lawn, which can grow bacteria and fungus. It also leads to a spongy texture of the soil as old, dead grass covers the soil. Roots may also start coming to the surface if they are lacking nutrients and proper aeration, which increases sponginess.
If the grass continues to grow too thick, eventually, all the grass in that area will die, and smother the soil, making it hard for other grass to inhabit the area.
What Does it Mean to Have a Thick Lawn?
Having a thick lawn isn’t inherently bad, as long as it isn’t too thick. Having too thin of grass can be bad as well, so it is important to find that balance.
Specifically, a thick lawn is when there is a lot of grass bunched up together. Usually, it is thick enough that you can’t see or feel the soil underneath when stepping on it. It tends to have a springiness, but not a sponginess.
What Causes a Thick Lawn?
When looking for grass to cover a lawn or area, looking for grass that spreads via runners is usually your best bet. These have roots that ‘run’ either above or below ground. As these roots stretch out, they produce more plants.
Since the roots are all connected, they are good even for covering up small inhospitable patches you may come across on your lawn, though it may take longer than the other areas.
What Exactly is Thatch?
Thatch is what occurs when dying stems, leaves, and roots build up in an area. As the thatch grows, it eventually traps fresh, new grass leaves and stems inside of it. Eventually, this can produce ‘dead’ patches on your lawn where nothing can break through the thatch to continue growing.
Thatch has other issues as well. It can keep the soil moist, which increases the chance of fungus and diseases that can harm your grass. It also can block water, fertilizer, and fresh air from entering the soil and getting to the roots.
Are Certain Types of Grass Thicker than Others?
Sometimes, the thickness of your lawn depends on the soil, fertilization, and water. However, the type of grass you use also influences the thickness. Some grass naturally produces thicker patches, while others tend to spread out far and leave large gaps between.
Some examples of popular thick grass include:
- Bermuda Grass
- Centipede Grass
- Zoysia Grass
- Kentucky Bluegrass
- Tall Fescue
These are some of the most popular. However, depending on where you live and what you want your grass for (feels soft on your feet, self-maintaining, can handle heavy foot traffic, etc) there are many other types available as well.
It’s also important to do your research when buying thick grass for your lawn as it can be misleading. While many types of grass grow thickly, some only do it in isolated patches, instead of running across a lawn.
How to Thin Grass That is Too Thick?
1. Rake the Lawn 
Using a rake is probably one of the most common ways to thin grass. There are various tools you can use, such as thatching rakes, power rakes, and vertical mowers. However, many people use their normal rakes, though it does take a lot more effort.
Read our article on Power Rake vs a Dethatcher to learn more.
Just like you would normally, you rake up your grass (yes really) focusing on pulling out those thick clumps of dying and dead roots and grass. While it is always a good idea to focus on the dead patches, try to do all of your grass to prevent any further problems.
This is the easiest and cheapest way to do it, but it will take a lot of time and energy.
2. Use a Dethatcher
A dethatcher is another tool that is designed specifically for thinning out a lawn. It is used when the thatch is already very thick, usually over half an inch. They are motorized to allow for the most power to rip out the dead patches.
However, if you have a bigger lawn and a tractor, they have more simple dethatchers that are just an extensive raked attached to the back of a truck or tractor.
Be careful when using this method, as it can easily damage the turf if you aren’t careful. As it is just a motorized or dragged rake, if it goes too deep into the soil, you risk ripping up your healthy grass and soil as well.
3. Verticutting
Verticutting is a relatively new technique, so if you haven’t heard of this before, don’t be surprised. Like the other two options, it removes the thatch buildup on the lawn to allow the grass to grow and thrive.
It cuts through the thatch and brings it up to the surface without hurting the grass or the soil. Like dethatching, it requires a special tool. The verticutter can be set to a certain thickness, depending on the type of grass you have. Most grasses can probably be set with the blades around three inches apart while thick grasses like Zoysia and Bermuda will do better with the blades only one inch apart.
The important part of verticutting is to make sure you fully water your grass a few days beforehand.
Thick Grass FAQs
Can Grass Thin Out on its Own?
Whether your grass thins out and spreads on its own depends a lot on the grass you are using. Grass with runners, either above or below ground will eventually spread out and fill in the bald spots.
Grass also dies off by itself as it is packed in, causing it to naturally thin. However, without proper raking up of dead grass, you still experience the spongy texture and your grass may eventually grow too thin or get bacteria and fungus growing in the area.
Can Your Lawn Be Too Thin?
Some grasses just grow in thinner patches than others. However, sometimes grass may just be too thin due to not having enough nutrients. Adding fertilizer to the soil can help.
Another common reason is cutting your lawn too much. If you cut your grass too low to the ground or thin it out too much, then you risk your grass not being able to photosynthesize and as a result, it will slowly grow thinner over time.
Read our article on How to Thicken a Thin Lawn here!
Why Do I Have Patches of Thick Grass?
The most common reason is that you may have different types of grass on your lawn. This is pretty common as the different types allow to cover all soil types. Some grasses might grow faster and thicker than others.
Additionally, some soil might be full of nutrients, allowing the grass to grow faster and thicker in certain areas.
Can Thick Grass Cause Your Lawn to Be Spongy?
Grass that is too thick will cause a lawn to be spongy. This is because the roots have no place to go except to the surface. This increases sponginess. But what causes sponginess in the first place is the amount of thatch in your grass.
Cleaning out old, dead grass is the key to reducing the sponginess of your lawn.
Can Having a Thick Lawn Cause Lawn Fungus?
No, it is the opposite. Having a thick lawn can help prevent fungus. What causes fungus most often in lawns is overwatering, weak grass, or thin thatch. Thick grass can help reduce lawn fungus as it chokes out anything else that may want to grow.
However, if you have too thick of a lawn, you may end up with patches that smother themselves and lead to dead patches, which then leads to perfect areas for fungus to breed.
Final Thoughts
While having a thick lawn is the dream, be careful to not confuse a thick lawn with one that is far too thick. Similar to cutting your hair, trimming through the thatch and cutting down your lawn will help your grass in the long run grow thicker and healthier.
While you can thin your grass by raking up the thatch, that can take a lot more strength and power than you have. Both verticutters and dethatchers are a great way to reduce your effort and make it much easier for you.
Thankfully, grass doesn’t have to be thinned very often. Once every two or three years is more than often enough t keep your lawn healthy and thriving, no matter what kind of grass you have.
Jamie is the founder of The Backyard Pros. When he was 15 years old he started working at a garden centre helping people buy plants, gardening products, and lawn care products. He has real estate experience and he is a home owner. Jamie loves backyard projects, refinishing furniture, and enjoys sharing his knowledge online.