How to Know When Your Lawn Needs Dethatching—and the Best Time of Year to Do It

Fall is almost here—and with it, many homeowners are staring at the finish line of lawn care. Sure, there will be leaves to bag up and bushes to cut back, but the pressure of keeping your grass green and grub-free through the dog days of summer is practically gone. Job well done, right? Well, not so fast.

Turns out, fall is the perfect time to prep for greener days ahead, and a little strategic TLC can help you achieve a prize-worthy lawn next year. One important task to add to your fall lawn care to-do list is dethatching your lawn. Here's what you need to know about this process and exactly when it should be done.

What is Thatch?

“Thatch is the layer of dead grass, roots, and organic matter between the soil and your lawn,” says Teri Valenzuela, natural science manager at Sunday. “While up to one inch of thatch benefits your lawn’s moisture retention and temperature regulation, excessive thatch can suffocate new growth and available oxygen.” Even the best cared-for lawns can fall prey to thatch, which tends to build up due to over-fertilization, poor soil health, or excessive pesticide use, which can disrupt your lawn’s natural decomposition process.

When to Dethatch Your Lawn

Think of your lawn as a filter that has gotten clogged throughout the summer due to a steady stream of grass clippings and debris. This makes fall the ideal time to press the reset button. Fall conditions can also exacerbate the existing thatch. “When the seasons change and the leaves fall, they can leave behind extremely dense layers of leaves and leaf mulch,” explains Lawn Love pro Justin Stultz. “Erosion can start washing organic material and rocks or gravel into thick piles along your yard's natural drainage areas.

For best results, Stultz recommends dethatching your lawn just as the weather is cooling down for fall, or as the soil is warming up in spring. However, you shouldn't restrict yourself to only those two seasonal transition periods. "Ideally, you should dethatch any time you notice a layer of grass clippings or leaves over an inch above your soil," he says.

How to Dethatch Your Lawn

To properly dethatch your lawn, Valenzuela recommends homeowners start by mowing to the correct height (around 3 inches), then using a garden or dethatching rake to remove excess plant material. “You can pick up a manual thatch rake at any big box store in your area,” adds Stultz. “Alternatively, you can buy a battery-powered or plug-in version to save you a lot of time and backache.”

You can also incorporate better lawn care practices into your routine to prevent a thatched lawn in the years to come. “To prevent future buildup, maintain proper fall fertilization, keep your soil healthy, and select grass types like tall fescue or perennial ryegrass, which are less prone to thatch accumulation,” recommends Valenzuela.