Sunday, July 31, 2016

Yellow Mushrooms and Houseplants

Lantana and Leucocoprinus at the Butterfly House - Chris Barnhart

The question of the month has been "what are the yellow mushrooms in my plantings?"  It has cropped up twice in the lantana pot in the Butterfly House and is commonly seen in potted plants inside houses.  Meet Leucocoprinus birnbaumii, described in detail at

This mushroom has been called a flowerpot parasol, yellow houseplant mushroom and many other names reflecting its presence in gardening and potted plants.  It is native to the tropics and subtropics although the first descriptions were in greenhouses.  It is a saprophyte that lives on decaying plant matter and where does it find comfort in our temperate climate?  How about a greenhouse or a warm sun porch with potting soil and mulch in a pot.

I might argue that in Missouri L. birnbaumii meets my criteria of an invasive species, albeit a rather benign one.
  • It is exotic, that is nonnative to the ecosystem under consideration, i.e. the temperate midwest.
  • It is spread by humans to those regions, in this case in potted plants.
  • Causes environmental or economic damage or a danger to health.  While mild, the number of gardening sites answering questions on removing or preventing it suggests some folks are spending time and effort fighting it.
Later, parasol now open - Wikimedia
Some have suggested that it could be poisonous.  This is one more opportunity to tell your children to never eat a mushroom unless it is identified by an expert.  Don't let your pet eat it.  I have never seen any of our dogs eat a mushroom (although Duke eats everything else he finds outdoors.)
I would argue that it should be considered a bonus, an unexpected if somewhat temporary colorful gift from the soil.  Some resources have even proposed that florists should consider selling mushrooms in pots, or at least throw in a few L. birnbaumii spores with each purchase.