Are lawn fungi harmful?

When summers are rainy and the soil has a hard time drying out, fungi can appear on lawns. Although they do not pose a problem to the lawn, they are not very visually interesting and might cause problems for children or pets, if ingested. In the vast majority of cases, the mushrooms growing on your lawn are not edible, and can have negative effects when ingested. Some time and more sun will take care of a majority of the problem, but if the presence of mushrooms bothers you, here’s what to do.

Why are fungi growing on your lawn?

If mushrooms are growing on your lawn, it means that decomposing organic matter is undoubtedly present in your soil. It can be many things, such as :

  • An old, buried stump
  • Tree or plant roots
  • Compost that hasn’t finished decomposing
  • Too much thatch

Too much humidity, lack of sun that is not allowing the soil to dry out properly or poor drainage are all causes that can encourage fungus growth. The visible part on the surface is only the flower, the real problem is in the soil, often quite deep.

What to do to get rid of fungus

With a little patience, the problem will take care of itself. If the fungi’s presence bothers you, you can simply pull them out and put them in the trash, or go over them with the lawn mower. However, if you do not take care of the problem from the source, chances are the mushrooms will come back.

Here’s what to do:

  • Dig to see what is underneath your lawn. Find the decomposing organic matter, and dispose of it.
  • Aerate your lawn to make air and water circulation easier. Aeration will also reduce the layer of felt that’s on the soil surface, which can also be another food source for the fungi.
  • Avoid water accumulation by correcting drainage problems.
  • Prune trees that cast too much shade over your lawn, or replace the lawn by another type of grass that tolerates shady spots more.

Myths that won’t quit!


You might have heard that you must apply lime to get rid of fungi. It’s completely false. Lime is designed to modify the sol pH, and has no impact on mushrooms. It can definitely help your lawn, but will not get rid of the fungi.


Fungicides you may find in garden centers will also not solve the problem of mushrooms living deeply into the soil. In fact, they do not serve any purpose. In Canada, there are no fungicides certified for fungus control on the lawn.

If you’ve been having fungi problems on your lawn, it’s not a disaster! It is actually a sign that your soil is alive and well, but needs to be taken care of to stay healthy. Your Nutrite Expert can help you with the necessary corrective measures so that your lawn is not covered in mushrooms anymore.