Blog - Lawn Buddies

Why is My Grass Turning Brown After Mowing?

Written by Chase Coates | Nov 17, 2021

After you mow your lawn, it’s fun to gaze out over your perfect green carpet and enjoy the results of your hard work.

Look at that beautiful emerald green — whoa, wait a minute.

WHY IS IT BROWN??!!

Why is your grass turning brown after mowing?

Calm down and let’s take a look.

Dull Mower Blades

When’s the last time you sharpened your mower blade? A dull mower blade shreds the grass instead of cutting it cleanly. This causes the tips of the grass to die and turn brown. The jagged edges also invite pests and disease.



A sharp blade makes a nice, clean cut, which helps the grass to heal faster and stay healthy.

Mowing Too Short

We hear you doing the math. If you mow extra short, you don’t have to mow as often, right? Genius!

But mowing too short is also called “scalping.” If that sounds bad, you’re right. You’ll see brown patches if you cut into the crown of the grass and killed it.

Cutting your grass too short stresses the grass, and makes it more susceptible to damage from insects and diseases.



Each blade of grass is actually a leaf, and it needs enough surface area for the photosynthesis that fuels its growth.

If the dead patches are small, grass might grow back and fill in. Larger dead patches will need to be reseeded.

Never cut off more than a third of the grass blade at any one time.

That way, the grass will develop a deeper root system to support the longer blades and need less water. That leads to a fuller, greener lawn.

Your Grass Might Be Dormant

Just because your grass is brown after mowing doesn’t mean it’s dead. It might just be dormant, which means growth naturally slows down, and it becomes less green.

How to tell?

  • Give it a tug. If the plants pull out from the ground easily, they're probably dead. If the roots hold fast when pulled, the plants are dormant.
  • If your lawn is all the same color brown.
  • If you have cool-season grass, and there have been prolonged heat periods. If your grass is turning brown after mowing in summer, that could be it. Wait until your grass is in season to see if it starts growing back.

Don’t worry. If your grass is dormant, it will naturally green up again in the spring.

Maybe Your Grass Has a Disease

There are plenty of turf diseases in Idaho, and they can strike pretty fast.

Look closely. Is your lawn turning brown in patches? Lawn damaged by fungus will often have a brown dead spot where the grass has died, but a lighter yellow-ish-brown ring around that where the fungus is spreading.

Applying fungicides can help treat many diseases and revive brown grass. A professional lawn care technician can help with diagnosis and proper treatment.

Thatch Buildup

Your lawn might be suffocated by a buildup of thatch.

This can happen when you wait too long to mow the lawn (we’re not judging) and you don’t bag the clippings.

The long clippings settle into the lawn and turn brown. You’ll notice this brown thatch first.

Then, the thatch blocks sunlight from reaching the lower portion of the grass blades, causing them to die.

Grass Looks Dead After Cutting? Get Pro-level Help

Whatever the reason, brown grass understandably freaks you out.

Why not turn to the pros?

Lawn care pros can help you diagnose why your grass is turning brown after mowing, and boost your lawn’s health so it returns to its healthy green self again.

Is Your Lawn Ready for a New Best Friend?

If your grass is brown after mowing, it might need a new best friend.

Choose an Idaho Falls or Boise professional lawn care service that bundles your yard’s most-needed treatments into one convenient, no-fuss plan.

Fertilizing, weed control, grub control. Done.

We’ve got your back.

Got a few minutes? That’s all you need to get started.


Then kick back and relax in your healthy, thriving yard.

Image Source: blade of grass