So you have mushrooms dotting your lawn. Congratulations! Wait, you mean no one has ever congratulated you on your mushrooms before? You think mushrooms are just weeds? Think again.
To successfully get rid of mushrooms, cut off the mushrooms at the base and remove. Ensure that you’re not overwatering your lawn and remove excess decaying carbon sources to avoid mushrooms popping up. Don’t apply fungicides, as they’re meant for fungal diseases and ineffective against mushroom’s deep roots.
Are Mushrooms Even Bad for my Lawn?
Mushrooms are not bad for your lawn. They’re actually a good sign that your lawn soil is healthy!
Mushrooms are the blooming fruit of an underground network of fungal threads known as mycelia (or hyphae). When conditions are dark and wet, the fungi send up fruit to reproduce by spreading spores. (They can even create their own breeze to do this!) Most of the year, they remain unseen and underground, aiding the surrounding plants.
How Mushrooms Help Your Lawn
Mushrooms feed your lawn
Fungi feed on decomposing plant material and wood and convert it into nutrients that plants — like your lawn — can absorb. Because they decompose organic matter, they improve the soil’s structure too.
Mushrooms support perennials
Many species of fungi form a mycorrhizal relationship with woody perennial plants, shrubs, and trees. The plants provide sugars to the fungi and the fungi make minerals available to your plants that they wouldn’t otherwise be able to absorb.
Mushrooms improve carbon sequestration
Studies have found that fungi sequester carbon and continue to do so even after the trees have died. They even help trees absorb CO2 faster. They’re an important part in fighting climate change.
So when you see mushrooms blooming, you know that underneath the soil, there’s a network of fungi that are helping your lawn and garden grow healthy, strong, and resilient, without you spending more and time on fertilizer.
Mushrooms to Watch Out For
While most mushrooms are harmless, there are a few to watch out for.
Mushrooms growing on trees
Pathogen fungi attack sick, injured, and stressed trees, not your lawn. These aren’t the mushrooms that pop up in the middle of your lawn. You’ll find them growing on trees, especially in open wood. When you spot these kinds of fungi, call an arborist for an evaluation. The fungi will continue to weaken the tree as it digests the wood, leaving either a dead tree or one easily knocked over in a windstorm.
While most mushrooms aren’t toxic, there are a few species that are. If you have pets and/or children that are likely to put anything they find in their mouths, then you need to keep watch. Identify the mushrooms that pop up in your yard. If your yard has toxic mushrooms, then work with a local extension office for removal, and keep pets and children away from them.
If you suspect that your dog or child has eaten mushrooms, take them to emergency care. Better safe than sorry.
Also, unless you’re well-versed in identifying mushrooms, don’t eat the mushrooms on your lawn. Again, better safe than sorry.
How to Prevent Mushrooms Growing in Your Lawn?
While the underground hyphae provide a valuable service to your lawn and there’s no way to prevent mushrooms from ever coming up (unless you can control the weather), take these steps to avoid the mycelia from fruiting.
Water less, especially in shady areas. Mushrooms thrive in shady, moist spots, especially those with a lot of rotting material. While you can’t do anything about a rainy season, you can water these spots less frequently, going for deep but shallow waterings and allowing the grass to dry out in between. This is actually better for your grass, anyway.
Water in the early morning. If you water in the evening or late at night and find mushrooms popping up over your lawn, switch to an early morning watering routine. That way, your lawn gets all the water it needs while any excess water on the grass will dry out quickly.
Core aerate compacted areas. Mushrooms spawn when they have damp and dark conditions. If the soil is compacted, water will sit on top of it, creating the perfect conditions. Use a core aerator to improve drainage. Less compacted soil will also help your grass grow healthy.
Remove excess thatch. While a thin layer of thatch is healthy, thick mats of thatch (over 1-inch thick) create the perfect environment for mushrooms – dark, wet, and stagnant. Dethatch your lawn to prevent this.
Remove excess rotting carbon or balance with natural nitrogen sources. Fungi feed on rotting carbon sources like wood and leaves (including buried wood), and prefer places low in nitrogen. So if you’re concerned, either remove the excess carbon sources from the area, or add more natural sources of nitrogen. The best balance for nitrogen to carbon is 1 part nitrogen to 10 parts carbon.
But don’t reach for synthetic nitrogen just yet! Your soil is healthy. Synthetic nitrogen will destroy all the beneficial microbiology and fungi, which I suppose will get rid of mushrooms, but will end up doing your lawn more harm. Plus, too much nitrogen will burn your grass.
To add more nitrogen naturally, leave fresh grass clippings on your lawn after mowing. They’re high in nitrogen. Thin them out so they decompose quickly before they dry out and become carbon sources.
How to get rid of mushrooms in your yard without killing the grass?
Just remove the mushroom heads with a rake or cut them off at the base. So long as conditions are moist, more mushroom heads will continue to pop up, so just keep raking. Once the wet season passes, the fungi will stop forming the fruiting bodies and go back to being an unseen helper.
Do not use fungicides. Because fungi grow deep underground, you will not kill them with any sort of herbicide or fungicide, and you’ll end up causing more harm than good. This kind of fungi in your lawn is actually good, remember. Fungicides are designed to be used on fungal diseases, like leaf spot, not on killing mushroom fungi.
Lawn Mushrooms FAQs
Why do I have mushrooms on my lawn?
Mushrooms in your lawn are a sign of healthy soil! For most of the year, they live as fungi below the soil, decomposing organic matter into nutrients your plants can absorb. When conditions are just right, dark and moist (like after days of rain), these fungi develop fruiting bodies that we call mushrooms, which seem to pop up aboveground like magic. The mushrooms spread spores to reproduce before disappearing.
Are mushrooms a sign of overwatering?
Mushrooms can be a sign of overwatering. Fungi need dark and wet conditions to produce their fruiting bodies (aka mushrooms). This could come from rain, overwatering, watering at night, or soil compaction.
Should I get rid of mushrooms on my lawn?
If you have pets or children who will nibble on potentially toxic mushrooms, or if you don’t like the sight of mushrooms popping up on your lawn, then remove the mushrooms by either raking or cutting them off at the base. Otherwise, you can leave them, as they’ll do your lawn little to no harm, and they’re a sign that your lawn is healthy. Using fungicides or synthetic nitrogen will cause way more problems.
How long do mushrooms last on my lawn?
Mushrooms will only last a few weeks after coming up. So long as conditions remain damp and dark with plenty of carbon material, the fungi hyphae below will keep sending up mushrooms. But once you either correct the overwatering or carbon matter, or the rainy season comes to a close, mushrooms will stop popping up.
Are lawn mushrooms edible?
While some mushrooms are safe to eat, other species are toxic. If eaten, they can cause symptoms ranging from an upset stomach to organ damage even days later. Take the side of caution. Many toxic varieties are difficult to tell apart from nontoxic ones. If you’re interested in foraging mushrooms, take a course with an expert!
Are lawn mushrooms poisonous for dogs?
While not all lawn mushroom species are poisonous for dogs, there are a few that are, including the Amanita family (Death Caps, which smell fishy), Inocybe, Clitocybe, and Lepiota species.
- Wobbling or loss of balance, a drunk walk
- Jaundice (yellow skin and whites of eyes)
- Sleep-like coma
If you suspect your dog has eaten a mushroom (and especially if they have the above symptoms!), take them to your vet, animal poison control, or an animal ER. Don’t wait. The sooner they receive treatment, the better chance they have. Take a picture of the mushroom if you can to help the vet identify it.
An ounce of forethought goes a long way. To keep your dog safe:
Take photos of the mushrooms that pop up in your yard and identify them. Your local university extension office can help with that! Because mushrooms are perennial, this will give you a good idea of what you’re dealing with. And if your dog does accidentally eat a mushroom, you’ll already know what species it likely is. If the mushroom is toxic, the extension office can help you figure out how to remove it.
Remove all mushroom heads in places where they can get at them and supervise when they’re outside off leash. If you can, avoid letting them off leash when mushrooms have popped up.
Jamie is the founder of The Backyard Pros. When he was 15 years old he started working at a garden centre helping people buy plants, gardening products, and lawn care products. He has real estate experience and he is a home owner. Jamie loves backyard projects, refinishing furniture, and enjoys sharing his knowledge online.