Why Mushrooms Grow in Potting Soil—and What to Do About Them

Rogue invader or pleasant pot-mate? You be the judge.
Rogue invader or pleasant pot-mate? You be the judge. | lawcain/iStock via Getty Images

Finding something unexpected around your houseplant is usually cause for alarm. Even the smallest insects can be a death sentence for plants when they invade a pot, and they should be dealt with immediately. But bugs aren't the only uninvited guests that can crash your planter. Fungi can grow spontaneously in potting soil, much to the surprise of many plant owners. If you spot a mushroom at the base of your monstera or philodendron, here's how you should react.

As Nola.com reports, it's normal to find mushrooms growing with potted plants. If your soil contains spores, whether they traveled through the air in your home or were there to begin with, you can expect mushrooms to pop up under the right conditions. Because these types of fungi thrive in warm, moist environments, you're more likely to encounter them in the summer months.

Mushrooms subsist on the dead matter in dirt, so you don't need to worry about them feeding on your houseplant. Your plant may actually benefit from the new pot-mates. According to The Sill, fungi lowers the pH in soil, which helps nearby plants absorb essential phosphates and minerals. Fungi and plants also communicate with one another through their roots. Plants use this connection to their advantage by treating their mushroom neighbors like a canary in a coal mine. If they sense the mushrooms are being attacked by insects, plants will preemptively activate their own defense systems.

While some plant owners welcome fungal visitors, others may wish to keep their potting soil clear. To get rid of unwanted mushrooms, pluck out caps as soon as possible and skim the top 2 inches of soil out of the pot and replace it with a fresh layer. This will hopefully remove any spores that have infected the pot. To prevent mushrooms from popping up in the future, try watering your plant less often (but still enough to keep it healthy) and move it to a cooler area of your home.

Not all plant problems are as harmless as a rogue mushroom. If your flora is looking worse for wear, consider these troubleshooting tactics.