Table of Contents
If you are planting a new garden outside and are using mulch, you may find some little mushrooms sprouting! It can be confusing or even frustrating if you weren’t expecting, but have no fear: Mushrooms growing on mulch is no problem to fear.
Mushrooms grow in a variety of climates in almost every part of the world, so it’s a natural outcome.
In fact, the mushroom spores that sprout mushrooms in your mulch were probably already present before you even laid it out. That’s how prevalent they are in everyday gardening supplies.
Remember, mushrooms are simply the fruit of fungus. Fungus particles are present in the air almost everywhere. It’s a natural factor in anything you grow, and only the bad fungus is what you need to worry about. Mushrooms are oftentimes not bad fungus to have in your garden!
Why do mushrooms grow in mulch?
As shared above, mushrooms can find their way into almost any soil. Some mushrooms grow well in enriched soil, and others grow well in wood-supplemented material such as mulch. The biodiversity in mulch presents an ideal growing space for many mushrooms.
Many mushrooms feed on the fiber present in mulch and the moisture also helps. All mushrooms need some level of moisture to grow. Since mulch is often very wet from watering consistently, it works for mushrooms to grow.
The other big aspect of mushrooms growing in mulch is the lack of competition. Mushrooms don’t do well in the face of other fungus or fast-growing species of plants, because they get outcompeted.
Even the presence of earthworms or bugs can prevent the spawning of mushrooms, because bugs will eat the mushroom mycelium before it can grow.
High quality, fresh mulch doesn’t have many contaminants or bugs, so the mushrooms can thrive.
Read more on why mushrooms grow the way they do in this article here.
Will mushrooms in my mulch harm the plants?
The short answer is no, mushrooms cannot harm whatever you plant.
In fact, the mushrooms can actually help your plant soil or mulch stay rich in the proper nutrients for plants to grow.
Mushrooms are a very important part of our ecosystem. They consume dead matter and turn it into fertilized, enriched material. The mushroom cycle produces material that helps your plants grow.
As long as the mushrooms aren’t too prevalent, then they won’t hurt. Chances are, the mushrooms you can find in your mulch won’t last long. Mushrooms only fruit for a week or two, and they are very cyclical.
As soon as a temperature swing or dry spell comes, the mushrooms will most likely vanish. The material they leave behind, however, will help keep your mulch strong and nutrient-diverse.
How to get rid of mushrooms in mulch?
If you just can’t stand the mushrooms in your mulch, there are a few ways you can prevent them from growing.
Stirring the mulch to prevent mushroom spawn
By moving around the top 1-2 inches of your mulch consistently, you will prevent mushroom mycelium from stabilizing and reaching the surface to fruit.
Mushrooms try to fruit into the air from the ground, so by keeping the top layer mixed, they don’t get an opportunity. This method can work well for preventing mushrooms growing in your mulch.
Drying out your mulch to prevent mushroom growth
Mushrooms need a good amount of moisture to grow properly. In a completely dry mulch, mushrooms will almost never grow. Of course, you can’t dry out your mulch completely because you need water for other plants to grow.
You can keep the top 1-2 inches of your mulch dry and this will help prevent mushrooms from fruiting out of your mulch. This may be hard, but if you use an in-ground watering method or try watering the mulch in small portions it should work.
You can also combine the 2 methods here by stirring the mulch frequently and only keeping the lower parts of the mulch wet to prevent mushrooms from spawning in the mulch.
Using the sun to dry out mulch
As an addendum to the above, you can also let the sun do the work of keeping the soil dry. If you are laying mulch in a shady area, then the sun does not have a chance to dry the soil.
With consistent sun, the top layer of your mulch won’t retain the moisture that mushrooms need. This is a natural defense against mushroom growing.
Introduce some sun and you should see less mushrooms, as long as you don’t waterlog or water the mulch every day.
You may need to clear overhead branches to allow sun to hit your mulch for some parts of the day.
Introduce worms or other mushroom-eating bugs
Earthworms and other mulch bugs will consume the mushroom mycelium before it has a chance to grow and fruit. This can be a reliable method to keep mushrooms out.
We recommend using worms because worms keep your soil properly enriched also. Worms effectively fertilize and keep mulch and soil healthy. This is a natural alternative to the above methods and it keeps nature at the forefront of your plant growth.
Using raised beds to keep mushrooms out of mulch
Another great method to keep mushrooms away from your planting activities is to keep your mulch in a raised bed. By isolating the mulch, you can help keep mushrooms from naturally finding their way into the soil.
This isn’t a guarantee, but if you deploy this method along with the above ones then it should work out in your favor.
Using a raised bed for your planters is also beneficial for keeping other mold and fungus out also.
Remember, fungus and mushroom spawn float through the air. A raised bed can still contain mushroom spores, because they travel via wind to reach their ideal growing space.
They can easily find their way into a separate bed! So this will help, but it’s no guarantee of not having mushrooms grow.
Not to worry, mushrooms don’t last long anyway!
As a final note, mushrooms don’t last very long like plants do. If you do see mushrooms in your mulch, chances are they will fruit for only a few days and then they will disappear. The mushroom lifecycle is much shorter than a plant lifecycle and they don’t stick around.
The mushroom mycelium underneath that you cannot see may remain there, but this can only help your mulch to remain nutrient-diverse, so don’t fret.
You can simply pluck the mushrooms if you see them and then discard them outside of your mulch. There is only some chance you will see them again, and it will be unlikely if you deploy any of the above methods.
Conclusion
If you use any of the methods outlined in our article, you should be seeing less mushrooms in your mulch or soil. All of our methods are using nature to your advantage, which is the best way to go about it.
Alternative to this post, growing mushrooms intentionally can be a very fun and rewarding experience. Read more about growing mushrooms on our site here: mushroomgrowing.org
