"Also, know as flowerpot parasol mushroom it’s a tropical species that often found growing from the commercial potting mix. The Leucocoprinus birnbaumii Mushroom is poisonous to dogs only in very large quantities."


"This is a common mushroom in flowerpots that colonizes rich organic materials. Rather than being a pest or a sign of something wrong, these mushrooms are a harmless sign of healthy soil. This type of mushroom is common in warm, humid climates or in indoor pots. The sudden appearance of these mushrooms in indoor potting soil especially can cause alarm and concern, but by and large, they are simply a sign of organically healthy soil. They do not harm the plants, are not known to be toxic, and do not need to be eradicated."

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After a week of very hot and humid weather, this lone mushroom suddenly popped up overnight in the soil with some potted Christmas Cactus cuttings. As seen above, one source says this mushroom species may be toxic; while a different source says it isn't. So when in doubt, I'm cautious and assume they are.

I have VERY small dogs. So what is a tiny quantity to a larger dog is massive to mine. Therefore, I moved the pot to somewhere they can't reach. Plus (after taking this photo), I also removed the lone mushroom from the soil. Hopefully more don't grow in with the cactus cuttings.