There’s a fungus among us! Mushrooms in your lawn can be unsightly, and sometimes, just plain odd-looking.
- What are they?
- Why are they there?
- Should you get rid of them?
- Will they harm your lawn?
If you have ever had a question about lawn mushrooms, you have come to the right place! Keep reading to find the answers to all your fungus inquiries!
What are lawn mushrooms?
The small mushrooms that poke out of your yard are a part of fungi. Most of the time, the fungus stays in the soil. Its role is to break down the organic matter that is in the ground. But, when the conditions are right, mushrooms will sprout out of the ground.
These mushrooms are the reproductive parts of the fungi. Once they are up, they spread spores. The spores are located under the cap. They are spread via the wind or animal consumption. When the mushroom dries out, it disappears again.
Are mushrooms bad?
Mushrooms are not necessarily bad. They may look unsightly to you, but they are actually an indicator that your yard is full of rich, organic material. The fungus that creates mushrooms is actually breaking down all that material to build healthy soil.
However, there can be damaging fungi in your lawn. If you have a wet property with poor drainage, these fungi can develop and kill your grass.
What are the different types of mushrooms?
Mushrooms can come in a wide variety of sizes, shapes, and colors! There are many, many varieties of fungi with mushrooms that could sprout up in your yard. Here are a few of the most common types.
Fairy rings
A fairy ring fungus looks like a circle or semicircle of green grass. It can be anywhere from 1-12 feet across. It may or may not have mushrooms. Fairy rings can live for many years. They will usually expand, and the center portion of the fungus will die out as it grows outward.
Fairy rings are typically not too hard on the grass. Sometimes, however, the underground fungal growth in the center of the ring will become very dense, and the grass will start to die. If this is the case, the center of the fairy ring should be aerated to break up the dense underground fungus. This will allow water and air to reach the roots of the grass.
Inky caps
These common mushrooms look white when they first pop up, but the cap turns to a dark liquid. Clumps of these mushrooms show up after it rains from spring to fall. They are harmless but can be messy!
Mycorrhizae
These beneficial fungi are usually attached to plant roots. Oaks and pine trees cannot grow well without mycorrhizae to help them absorb water and nutrients from the soil. Sometimes, mushrooms from these fungi will show up in the grass nearby.
Armillaria mellea
This fungus, also known as armillaria root rot, can kill plants and trees. It produces clusters of tan mushrooms in the fall. Once the mushrooms show up, the plant or tree is usually in its final stages of decline.
New lawn mushrooms
New sod requires a lot of water! Mushrooms also like a lot of water. It is pretty common for small, harmless mushrooms to pop up in new sod. Panaeolus foenisecii are small with brown, cone-shaped caps.
Conocybe and Clitocybe mushrooms may also appear. They are also small, with lighter caps. Once the sod is established and needs less water, these mushrooms usually disappear.
Black mushrooms
These mushrooms usually come from yard waste, mulch, or grass clippings. They are not harmful and can be easily removed if desired. If they are persistent, try to improve the drainage in your yard and clean up all debris to discourage further growth.
Why do I have mushrooms growing in my yard?
Usually, mushrooms are just a part of a healthy, growing lawn. Remember, they are just the visible part of an underground fungus system. That system is building rich, healthy soil to feed your lawn.
Other times, mushrooms may be an indicator that there is something you need to adjust with your lawn and garden routine.
Compacted soil
Sometimes, mushrooms sprout because your yard has poor drainage. Check your lawn for standing water after rainfall or watering. If your soil is compacted, the water will not drain down to the roots of the grass.
Aeration
Aeration removes plugs of soil. This allows oxygen and air to reach the roots of the grass. Water will drain. A yard with good drainage should help discourage excessive mushroom growth. You can buy an aerator, rent one, or you can hire someone to aerate your lawn for you.
Dethatching
Dethatching removes the thatch or the layer of grass next to the soil. It can build up and block proper water drainage into the soil. Dethatching rakes are available for purchase or rent, or you can hire a lawn company to dethatch your lawn.
Old plant matter
Mushrooms will pop up on rotting plant material. If you have old stumps or tree limbs in your yard, remove them. Even the old roots of an old tree may encourage fungal growth, so you need to remove them entirely.
Grass clippings and old leaves may foster mushroom growth. If you mulch your grass and notice more mushrooms, try bagging your clippings for a few weeks.
Pet waste
Pet waste will encourage fungal growth. Frequent animal waste removal is a simple way to combat this problem.
Too much shade
Water will not evaporate quickly from shaded areas. If trees shade your entire yard, you may experience increased fungal growth. Trim back trees and bushes to allow more sunlight to reach the grass.
Are mushrooms a sign of overwatering?
Mushrooms can definitely be a product of an overwatered lawn! If you have new grass or sod, it needs extra water. A few small mushrooms may pop up as well.
If your lawn has good drainage and sunlight and is still getting a lot of mushrooms, adjust your watering schedule. Try watering every other day, and only water in the morning. The cooler night temperatures and a damp lawn will encourage mushroom growth.
Can mushrooms help your lawn?
Some mushrooms are beneficial! The Mycorrhizal fungus is necessary for oak and pine trees to grow strong. This fungus attaches to the roots of the trees and helps them absorb nutrients and water from the soil.
Other mushrooms can help break down the organic materials in the soil to help. Mushrooms are often a sign of healthy, productive soil.
How do I stop mushrooms growing on my lawn?
If your yard is watered properly and drains well, yet mushrooms are still a problem, you may need to take extra steps. Before you consider a fungicide, make sure that your lawn is properly aerated, dethatched, and trimmed. Clean up any decomposing plant matter. Often these steps are enough to curb mushroom growth.
Beneficial mushrooms are easy to remove by just breaking them off at the base. The underground fungal network will still benefit your soil. You are just removing the unsightly portion of the mushroom.
How do you kill mushrooms without killing grass?
If your yard is home to a troublesome fungus, try a fungicide, like Scott’s DiseaseEx lawn treatment. It kills 26 different fungal diseases in most types of grass for up to four weeks. Apply the fungicide granules to dry grass with a fertilizer spreader, then water the grass. This fungicide will not harm your lawn.
Baking soda is a natural mushroom killer! It will raise the pH of the soil, which hinders fungus growth. For every gallon of water, add two tablespoons of baking soda. Mix well and spray on the mushrooms. Repeat as needed. If you spray this mixture on your grass, spray lightly. Too much baking soda can damage the grass.
What can I spray to kill mushrooms in my yard?
If you are looking for spray-on fungicides, try BioAdvanced Liquid Fungicide. It protects lawns against dangerous fungi for up to one month.
For a natural fungicide, try apple cider vinegar. Mix one cup of vinegar with four cups of water. Shake it up, and spray directly on the mushroom. Avoid getting any of the vinegar mixture on other grass and plants because it will kill them as well.
Are lawn mushrooms poisonous to dogs or cats?
We all want our pets to remain healthy! If you have unidentified mushrooms in your lawn, try to prevent your pets from eating them.
The Amanita and Galerina species of mushrooms contain Amatoxin, which is toxic if ingested. If you are concerned your dog ate a poisonous mushroom, contact your veterinarian. The common symptoms of mushroom poisoning are staggering, panting, whining, dizziness, vomiting, lethargy, and collapse.
If it is at all possible, use gloves to pick the suspicious mushrooms. Bring the bagged mushrooms to your local county extension office for identification.
Should I leave mushrooms on my lawn?
If you are not bothered by the appearance of mushrooms, there is no harm in leaving them alone. Most mushrooms will not harm your lawn and are just a sign of healthy soil. If left alone, the mushrooms will eventually release spores, then shrivel up.
Spore release may cause further mushroom growth if the conditions are right. If you already have a lot of mushrooms, you may want to remove them before they have a chance to release their spores.
Use a knife or trowel to remove the mushroom at its base gently. Seal it in a trash bag so that no spores can escape, then dispose of the bag.
What happens if you step on mushrooms?
Mushrooms are the fruit of the fungus. The cap of the mushroom contains spores that will be carried by the wind or your shoe when you step on them.
Final Thoughts
Mushrooms do not have to be a problem! Most of them are harmless. View them as a sign of a thriving lawn!
If their appearance bothers you, they are easy enough to remove. An overgrowth of mushrooms may be a sign that your yard needs less water or better drainage. Evaluate your lawn to determine if you need to make any changes.