February 11, 2021
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Lawn dethatching guide

Thanks for visiting my Lawn Dethatching Guide!

Thatch buildup is one of the main reasons that your lawn may not look to your liking. It’s a very common problem that appears on almost all lawns at one time or another.

But First…

What IS Thatch?

Thatch is a thick, sponge-like layer of dead organic matter that, over time, builds up between grass and its roots.

It consists of dead leaves, roots, stems, and similar material.

In normal circumstances, these items would do a lot of good for your lawn, as they usually decompose and provide nourishment for other plants.

But, when there is an excessive amount of this matter piled up because it builds quicker than it can decompose, it negatively affects the grass growth.

Thick and dense thatch layers prevent air, water, and nutrients from getting to the soil and grassroots.

This stresses and weakens the grass, eventually causing it to die out. Also, thatch buildup can have a bad long-term effect on the soil, so even after removing it from a certain area, the new growth will be hindered and sparsed.

Furthermore, it can become a breeding ground for fungus, parasites, mosquitoes, and other menaces that infest your lawn.

Several things can lead to thatch buildup

Some are related to the way you take care of the lawn, such as:

  • Overfertilization
  • Overwatering
  • Too much acidity
  • Or even irregular mowing.

Others are more natural, like:

  • Lack of the earthworms in the soil
  • The properties of the plants themselves

For example, Kentucky Bluegrass has underground stems that are hard and take longer to break so instead of being cut down while mowing they remain and take part in thatch buildup.

Excessive thatch buildup won’t just disappear by itself.When the layer reaches the worrying level, you’ll need to dethatch your lawn to allow your grass to preserve its health and continue growth.There are several ways you can go about this:

  1. You can call lawn care professionals and allow them to take care of your problem.
  2. If you prefer to save some money and do the job yourself, we have prepared a guide that will help you go through all of the necessary steps to dethatch your lawn like a pro.

Lawn Dethatching Guide, How to Dethatch a Lawn

While dethatching is one of the physically hardest and most daunting lawn care activities, it’s quite simple and can be finished within a day. Bear in mind, you’ll most likely have to do this every two or three years.

Step 1: Determine Whether You Need to Dethatch Your Lawn

Thatch Patches in Lawn

Some signs that you need to dethatch are obvious and can be spotted with a just quick glance over your lawn. If you have thatch buildup, you’ll probably notice brown patches in the areas where the thatch has almost completely suppressed the grass.

In other areas, your grass may be weaker, with blades thinner and further away from each other. When it rains, pay attention to see if the water runs off rather than being soaked into the ground.

Try parting the grass, as if you were parting your hair, and check if you can see the soil or just the thatch layer.

Also, when walking over the lawn with the excessive thatch buildup you may experience sort of “springy” feeling similar to stepping on a sponge.

To make sure your lawn needs dethatching, do the following:

  1. Use a sharp trowel or a shovel and dig out a small section of grass and soil, no more than 6 inches in diameter.
  2. Pull it out and you’ll certainly see a brown layer at the base of the grass. If that layer is less than an inch thick, your lawn should be fine.
  3. If it’s thicker it prevents the normal water and nutrient flow. In this case, you’ll have to dethatch your lawn to preserve it.

Thatch Layer

When is the Best Time to Dethatch Your Lawn?

The best time to dethatch your lawn is when it’s at its strongest. So, early in the growing season – early spring or early fall, depending on the type of grass you have.

Dethatching can be done in the other periods of the year, but your lawn will have a much harder time recovering. Additionally, since dethatching is so physically demanding, you’ll want to avoid hot weather making your job even harder.

Step 2: Preparation

  • Mow the lawn as it will help you reach the thatch layer and easily observe the dethatching progress. This will also help you remove some of the thatch debris of the top and prevent the ripping and tearing of the grass as you rake through it. Make sure you collect the cuttings.
  • Clear the lawn of any twigs, doggy bones, small rocks, or any other debris that can damage the dethatching machine.
  • Clearly mark any objects standing above the ground’s surface. This includes sprinkler systems, utility lines, pathway lights, large rocks, and similar objects.
  • Prepare all of the necessary equipment. Power rake (walk-behind dethatcher, similar to the lawnmower) is rather expensive and you’ll need it very rarely, so your best option is to rent it from the rental equipment store. If you have neighbors with similar thatch problems consider teaming up and splitting the rental costs.
  • Also, you’ll need a manual dethatching rake and a regular rake. If you own just a small lawn, then you’ll probably be able to get the job done with just the manual tools.
  • Prepare garbage bags where you will store the thatch debris. And, trust us, there will be plenty of it.
  • Make sure you have a hose connected to a water source for watering the lawn after the job is done.
  • Prepare fertilizer to feed your newly dethatched lawn.

Step 3: Dethatching

  • You can rent a Lawn Dethatcher (AKA Power Raker) for the day from Home Depot or Lowes, but they’re not that expensive and can be purchased from Amazon for a reasonable price.

Lawn Dethatcher

  • Before you start dethatching the whole area of your lawn, make a couple of several feet long passes with your power raker (dethatcher) set at different heights. Once done, check the debris to see how much of the thatch you’ve managed to pull out and if there’s too much of live grass in it. When you feel that you’ve found the right height, proceed to dethatch the whole lawn.
  • Start at the one side of the lawn and make one pass in a straight strip, similar to what you may do with the lawn mower. When you reach the end, turn around and do the next strip in the opposite direction. Always push your power raker forward, never go backward.
  • Once you’ve gone through the whole area, it should be covered with a ton of debris. Unless your Lawn Dethatcher has a collection bag like the image above, (check it out on Amazon here) you’ll want to pick up the regular rake and clean up the debris. Collect the thatch debris and deposit it in garbage bags.
  • Alternatively, you can use the lawn mower with a bag to collect the material, but due to the sheer quantity of the debris you’ll probably face, emptying the bag numerous times may take much more time than the manual raking.
  • After you’re done with cleaning start up the power raker again and cover dethatch the area once more. This time the stripes should be at the 90-degree angle compared to the previous direction. If some of the grass was folded over, blocking the access to the thatch, this time around you can easily uproot all of the dead debris.
  • When you’re done with power raking, the lawn should already gain a much healthier look. On close inspection, you’ll see that much of the thatch is gone. Of course, you’ll want some of it to remain under the grass to its various benefits which we discussed earlier.
  • Now, check the whole lawn area to see if there are any spots where you didn’t manage to uproot the satisfying amount of thatch. A lot of it is broken down by the power rake but not pulled out.
  • Since the grass has already taken some beating from previous crossings, you don’t want to go over it with the power rake again. This is where the manual dethatching rake comes into play. It has curved teeth on the one side and straight ones on the other.
  • For dethatching, you’ll want to use the side with straight teeth. Go over the whole area and try to collect any remaining thatch and loose debris. Spot dethatching is the most physically strenuous part of the job, and you’ll certainly feel it hard on your legs, back, and arms. When finished, once again collect the debris with the regular rake.

manual dethatching rakeIf you’re more a visual learner, here’s a quick 3 minute video showing how to use a Thatching Rake on your lawn!

Step 4: What to Do After Dethatching the Lawn

Seed Spreader

As soon as you’ve finished, water the lawn and fertilize the turf. This is also a great time to overseed your lawn.

(See My Article, How to Overseed Your Lawn for Step-By-Step Instructions on that!)

Introducing some premium seeds will help you revitalize your lawn and prevent future thatch buildup.

After a few weeks, depending on the weather conditions and the type of grass, the lawn should fully recover and you’ll be surprised how good and healthy it looks.

As for the debris you’ve collected, you can compost it for your garden, but only in the case that your lawn wasn’t chemically treated or overflown with weeds.

Take steps to prevent future issues with excessive thatch. Water, fertilize, aerate, and mow your lawn regularly.

Mow at the height of about 2-3 inches so that air and water can freely flow and reach the thatch layer and speed up decomposition. Mulch lawn cuttings and fallen leaves to accelerate the development of good bacteria.

Check pH levels of the soil regularly and seek expert advice on what to use to balance it. Following these steps will help you nurture a green, lush, thick lawn that you can be proud of.

Daniel Simmons

About the author

TheLawnMowingKing.com brings my 25 years experience as a professional gardener and landscaper to you!

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