How to Dethatch Your Lawn

Watering, mowing, fertilizing - these are lawn care essentials, but did you know that dethatching is a critical part of keeping your lawn healthy and strong? Read on to learn why.

WHAT IS THATCH?

Thatch is the undergrowth layer of steams, roots, stolons and rhizomes between your beautiful, green lawn and the soil surface. One inch of thatch between your soil and very bottom of grass blades is pretty normal. Any more than that can cause issues.

WHY DETHATCHING YOUR LAWN IS IMPORTANT

Thatch typically won’t get in the way of having a beautiful lawn as it’s a natural part of grass. It’s excessive thatch that you’ve got to watch out for, as too much thatch increases the amount of water your soil retains and that can lead to root rot, fungal issues and insect infestation. Excessive thatch can also prevent new grass shoots from growing. In other words: uh-oh.

THE CAUSES OF EXCESSIVE LAWN THATCH

There are a few reasons why your lawn would have excessive thatch: #1: Over-fertilization with nitrogen-based fertilizers. The most common cause, overuse of fertilizer, will cause extreme grass growth which, in turn, causes extreme thatch growth. #2: Unhealthy soil conditions. For example, a soil with low ph (acidic) below 5.4 will be missing key microbes that naturally break down thatch. (Want to know if your soil is healthy or needs nutrients? Every Sunday lawn care subscription comes with a complementary soil lab test.) #3: Overuse of pesticides. They have one job: to kill weeds and disease. But this often comes at the expense of killing earthworms that naturally burrow through thatch, moving it from the surface deeper into the soil where it can decompose due to healthy microbial activity. FUN FACT: A few cool season grass types have more potential for thatch issues. Those include bluegrass, creeping bentgrass and fine fescues. Grass types that have reduced thatch issues include tall fescue and ryegrass.

HOW TO KNOW WHEN YOU’VE GOT EXCESSIVE THATCH IN YOUR YARD

Take a quick peek at your lawn. Does it look more tan in color and less green? You can also quickly drop to your hands and knees and push the blades of grass aside to check out thick and dense your lawn thatch is. Deeper than an inch? Tightly woven together? It’s time to dethatch your lawn.

HOW TO DETHATCH YOUR LAWN LIKE A PRO

Ugh. Got a thatch problem? It’s nothing a little proverbial elbow grease can’t fix. Step one: mow. Then use a dethatching rake that looks similar to the OG garden rake. The tines of a dethatching rake dig into the thatch and pull it upward. Give your yard a good dethatching rake and, when the chore is complete, compost the thatch. You can also enlist the help of a power rake to speed up the process, but just be careful. These tools can harm your lawn if too much thatch and healthy grass is removed in the process.

WHEN TO DETHATCH YOUR LAWN

Always dethatch before you aerate your lawn, and dethatch as you see a problem with excessive thatch arise during the growing season.

3 WAYS TO PREVENT EXCESSIVE THATCH IN YOUR LAWN

  • Don’t over fertilize. It’s that simple.
  • Add soil amendments at least annually to increase OM which, in turn, will benefit soil microbes.
  • Use IPM method herbicides when treating issues like weeds.

PRO TIP:  When choosing grass for a new lawn, choose appropriate seed for location and sun, but also consider grasses that have lower potential with thatch issues.

PARTING SHOT: MICROBES ARE YOUR FRIEND

A healthy, beautiful lawn is a lawn full of life. And that includes friendly microbes. These little guys work quite hard for you to keep your grass healthy and strong. They break down thatch to keep it at a healthy level. Keep your lawn’s microbes happy by keeping your lawn’s soil healthy with nutrients that contain humic acid, seaweed, and microbial amendments. They also dig peat moss and organic matter like compost.