Mushrooms in houseplant pots
Small yellow mushrooms that pop up in potting mix; they don't harm the plant but are poisonous to eat.
What you'll see
- Lemon-yellow mushrooms 1 to 3 inches (2.5 to 7.5 cm) tall with bell-shaped caps, alone or in clusters.
- They appear in damp potting mix, and can come back again and again.
- A white or gray mold film may also form on the mix when it stays moist.
Why it happens
The fungus lives in the potting mix and breaks down dead organic matter. It arrives in the mix or as airborne spores, and fruits when the mix stays warm and moist.
What to do
- No need to treat: the fungus doesn't harm living plants, and sprays won't get rid of it.
- Pick the mushrooms off as they appear if kids or pets live with you, since they are poisonous.
- Let the top of the mix dry between waterings, or scrape off and replace the top layer.
Keep it from coming back
- Water only when the top inch (2.5 cm) of mix is dry.
- Space pots for good air flow so the surface dries faster.
Sources
- Iowa State University Extension: Will yellow mushrooms harm my houseplant?
- University of Maryland Extension: Algae and fungal growth on the soil of indoor plants
- University of Washington Miller Library: Yellow houseplant mushroom called Leucocoprinus
General guidance, not a diagnosis. For valuable, edible or outdoor crops, check with a local extension service or plant expert. Use any product exactly as its label says, and keep children and pets away while it dries.