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Dethatch Your Lawn

Every lawn is unique, and ensuring that yours is prepared for a long and healthy life means proactively managing issues as they arise. Knowing when your lawn is in need of a dethatching and having the understanding of how to do it properly will keep your lawn beautiful and strong for years into the future.

In this article we’re going to explore how, when, and why to dethatch your lawn, as well as cover some of the most important questions that will arise throughout the process.

What Is Thatch?

Thatch can be best described as a cross-section of soil and grass roots that presents itself atop your lawn as organic debris. Thatch is a mixture of living and dead plant materials that forms near the base of grass where the stem meets soil and roots. In a healthy lawn, small organic matter – such as grass clippings and mulched leaves – will break down quickly and be invisible at surface level. However, some materials take longer to decompose, and when the amount of organic

matter build up begins to outpace the breakdown, thatch will begin to thicken throughout your lawn.

It’s important to note that not all thatch is bad, and that there is actually a benefit to having some visible for short periods of time. A thin layer of thatch – ½ inch thick or less – will act as an organic mulch to your lawn and help conserve soil moisture. This will protect the grass against fluctuations in the soil temperature and ensure that it remains healthy over time. Additionally, thin thatch layers will also allow nutrients and air, alongside water, to better penetrate the grass’s soil.

Thick thatch – 1 inch or more – on the other hand, can have a detrimental effect. Due to its density, the thick thatch will prevent water and fertilizer from reaching the grassroots, and those same roots will often get trapped in the thatch itself. In a sense, thick thatch will prevent air and water from getting to or from the grass, suffocating it over time.

When to Dethatch Your Lawn

Prior to jumping into a dethatching project, it’s always best to assess your grass and determine whether the current thatch levels are healthy or not. The easiest way to do this is by taking a trowel, cutting out a small wedge of your lawn, and pulling it out for measurement and review. If the thatch is less than a ½ inch thick, don’t worry about it. If it’s 1-2 inches thick (or more), you’ve probably already started to see some lawn discoloration

and weakness, and it’s certainly time to get your lawn dethatched.

Similar to other lawn and plant projects, it’s best to coincide your efforts with the optimal growth season. This will ensure that your lawn has the best odds of making a quick recovery to full health. If you have cool-season grass, such as Kentucky Bluegrass or Bentgrass, your optimal thatching time will be late summer to early fall. If you have warm-season grass, such as Bermudagrass or Centipedegrass, your optimal thatching time will be during the transition from spring to summer. Note that you should never dethatch your lawn when it’s visibly dormant or stressed, as it can cause damage that won’t be repairable in the future.

How to Dethatch Your Lawn

A lawn dethatching project can be tackled on your own or with the help of a lawn care professional. If your thatch is 2 inches or more, it’s probably best to have someone perform the dethatching. Because the project may take more than a few sessions to complete, an expert will ensure that your lawn is able to make a full return to health. Any less than 1.5-2 inches and you should be able to tackle the project using any of the three following methods:

  • Manual Dethatching. You can manually dethatch your lawn using a dethatching rake. A heavy, short tool with curved blades, the rake is designed to dig into your lawn and pull up thatch as you move through it. A manual dethatching rake is great for light thatch removal projects, ongoing maintenance, and small lawn jobs.

  • Power Rakes. Think of this as a lawnmower with vertical blades. This dethatching tool will allow you to dig into thatch at the soil level and pull it up. It’s the perfect tool for larger lawns with thin thatch layers, allowing you to efficiently cover a large surface area.

  • Vertical Mowers. Otherwise known as verticutters, vertical mowers have long blades that slice through both the thatch and soil layers. This tool will pull thatch and grassroots to the surface as it works through the lawn, preparing it for a major overhaul. A vertical mower is best suited for lawns with very thick thatch or those in the process of renovations.

What to Do After Dethatching

Following the successful dethatching of your lawn, the next step is to seed the area and get it prepared for a full recovery to a lush, green state. You’ll want to select a premium grass seed to ensure that quality grass grows over time.

In order to prevent future thatch problems, test your lawn soil every three to four years. This will ensure that it remains at a healthy pH and nutrient level for sustainable growth. It is in your best interest to fertilize your lawn as often as necessary,

and if you have heavy or compact lawns, to aerate once every one or two years. This proactive maintenance will allow the grass to flourish without the threat of thatch.

What Causes Thatch?

Thatch is a dense mixture of both living and dead plant materials that form near the base of your grass, primarily where the stem connects with soil and roots. In a healthy lawn, the small organic matter – such as grass clippings and mulched leaves – will break down quickly and not be noticable from the surface level. However, some thicker materials will take longer to decompose. Thatch will begin to appear when the amount of organic matter build up on the lawn begins to outpace the material breakdown.

Although it will develop slowly over years, the compounded lack of matter decomposition on your lawn will be the primary contributor to thatch development, and if not dealt with in a reasonable amount of time, thatch will become a breeding ground for future thatch development and bug infestation.

Is It Better to Dethatch or Aerate?

When deciding on whether to dethatch or aerate your lawn, there are a few items you must take into consideration. To begin, thatching and aeration shouldn’t be used as a substitute for one another. Both provide unique benefits and the two should be used in combination to develop a healthy, lush lawn.

Aeration involves the removal of soil cores, including their thatch layer, creating a path for water and nutrients to access compacted soil. This process helps prepare the thatch for removal and speeds up the breakdown of the existing thatch on the lawn. Dethatching, on the other hand, helps to slice through the thatch and into the soil, removing the barrier of accumulated organic matter that has begun to suffocate the lawn.

By combining aeration and dethatching, you’ll be able to open your lawn up to growth, remove the harmful layer of thatch, and ensure that it’s prepared for the seeding and recovery stages.

Do Clippings Cause Thatch?

Yes, clippings are a contributing factor to thatch development on a lawn. For most healthy lawns, light organic matter – such as clippings – will deteriorate before they have the ability to compound into visible thatch, however, the combination of too much clipping residue, alongside mulched leaves and other material, will become the foundation of thatch formation on your lawn.

How Often Should I Dethatch My Lawn?

The decision to dethatch your lawn should be grounded in the quality of the grass and the long-term health prospects. As mentioned earlier, any lawn with a ½ inch of thatch or less should not be bothered, as the thin layer can be quite helpful to grass development. If you have 1 inch or more of thatch, it’s best to conduct a formal review and determine whether or not the layer is

beginning to impede grass health. If you aren’t comfortable conducting this assessment, you should call for the support of a lawn care expert in your area.

Once your lawn has been successfully dethatched and re-seeded, you shouldn’t need to take on a dethatching project for several years into the future. Yearly maintenance and quality checks will help ensure long-term grass sustainability.

Everearth is a leading landscaping provider in the GTA. With years of experience, we have the toolkit and industry knowledge required to ensure that your lawn is restored to a beautiful, green, lush state, regardless of its current condition. To learn more about our services, or to get a project quote, contact our team today.

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