There's nothing like walking barefoot on your lush green lawn—only to step on a squishy mushroom. Where there's one, there's probably more, and they can quickly become an eyesore. While mushrooms usually will not damage your lawn, their presence signals potential problems with your grass. Luckily, there are also prevention methods to help you eliminate pesky fungi from ruining the look and feel of your lawn.
Should You Be Concerned About Lawn Mushrooms?
Mushrooms aren't inherently problematic and can actually be helpful to a lawn in most cases. As the fungus feeds on the lawn's decaying organic matter, it breaks this matter down, making nutrients available to your grass. But some people have valid reasons for wanting to get rid of mushrooms growing in the lawn:
- They're considered unsightly, especially if you are preparing your property for the real estate market.
- Some mushrooms are edible (seek expert advice on which kinds are edible), while others are toxic plants, which can be problematic if young children and pets play on your lawn.
- Some mushrooms even stink badly, the most notorious example being the so-called "stinkhorns."
Causes for Mushrooms in Lawns
Mushrooms seem to spring up out of the blue. But this is not really the case. They are just the visible result of a process that has been going on underground for some time.
An underground fungus (with a much greater mass than the mushrooms have) is the true culprit of your mushroom problem. This fungus, often aided by poor drainage and a lack of sunlight, has been spreading as it feeds on decaying organic matter in the soil, examples of which can include:
- Dog or cat poop
- Fallen leaves
- Grass clippings
- Lawn thatch
- Old tree stumps that have not totally decomposed
The mushrooms are merely the reproductive structures of this fungus. Their purpose is to produce spores that can help the plant spread even further.
How to Get Rid of Existing Mushrooms
If the unsightliness or smell of the mushrooms bothers you, there are steps you can take to get rid of them. The job of a mushroom is to release its spores, so it's best to pluck and remove them before they can release their spores. This method will not solve the problem (because the underground fungus will live on), but it will cut down on mushroom reproduction in the future, at least.
Though timing is of the essence with this method, you'd have to become a mushroom expert to know when each species is about to release its spores. When plucking mushrooms from your lawn, try the following four steps:
- Pull or dig as much of it from the ground as possible (do not just pluck off the mushroom head).
- Put them in a plastic bag so the movement doesn't disperse any spores.
- Tightly close the bag so that no spores can become airborne.
- Spray a few drops of dish detergent mixed with water where you removed the mushroom; the dish soap acts as a mild fungicide.
How to Prevent Mushrooms From Growing
If you want to thwart the growth of mushrooms, you can take matters into your own hands. The overall reasons for lawn mushrooms include poor drainage, lack of nutrients, too many shady spots, and too much decaying organic matter left on the lawn. There are four steps to address mushroom problems:
- Encourage sunlight
- Lawn maintenance
The presence of mushrooms may mean that the soil underneath your grass is not draining properly. Poor drainage leads to overly wet conditions, which, in turn, can lead to lawn diseases and mushroom growth. Besides the mushrooms, you will know you have drainage issues when you see small puddles of water and muddy patches around your lawn.
Drainage issues could be the result of many problems, from having a flat yard, impacted soil, clogged gutters, or sidewalks that are blocking water drainage, for example. Some solutions let you drain your soil and water better or allow you to corral and harvest excess water. For example, to alleviate problematic waterlogging in your yard, you can:
- Reroute or extend a downspout and clean gutters causing flooding; water will then evenly distribute itself throughout the yard when this problem is corrected.
- Harvest rain to reduce poor distribution of water by creating a rain garden, rain pond, or rain barrels.
- Professionally install a French drain, swale, or dry creek bed for severe cases of flooding.
Aerate Your Lawn
Aerating your lawn may work in less severe cases. Aeration lets water and nutrients penetrate your soil rather than sitting on top of the grass. You can rent the equipment from a rental center since you won't need to aerate enough throughout the year to actually own the equipment.
Mushrooms love dark, damp patches of grass, so having too much shade encourages their growth. To alleviate this problem, prune larger trees and bushes to let more sunlight into your lawn area. You can prune small trees just enough to make a difference, and for larger trees, hire professionals.
Regular Lawn Maintenance
Dealing with the presence of decaying organic matter is largely a matter of cleanliness. If you consider yourself a "neat freak," then this step is right up your alley. You will never be able to remove all of the decaying organic matter in your lawn's soil (nor would you want to), but a concerted effort to keep the lawn clean can make a difference in the long run. To prevent mushrooms, keep up with the following lawn maintenance tasks:
- Make spring cleaning in the yard a priority annually.
- While leaving a small amount of finely shredded grass clippings on the lawn after mowing is generally a healthy practice for your lawn, consider bagging or raking them up if you are intent on keeping mushrooms from sprouting up.
- Rake fallen leaves off the lawn in the fall (or remove them with a leaf blower).
- Keep your lawn de-thatched.
- Remove old tree stumps completely.
Smith, Kevin T. “Beneficial and Harmful Mushrooms in the Landscape.” The Landsculptor. October: 31-34. October (2014): 31–34.
Alderleaf Wilderness College. “Poisonous Mushrooms.” Accessed July 28, 2021. https://www.wildernesscollege.com/poisonous-mushrooms.html.
Wilbur Bluhm, Marion County Extension Agent. “Lawn Pests and Problems.” Oregon State College, May 1959. file:///Users/mingui/Downloads/ECNO658%20(1).pdf.