How to Grow Mushrooms in the Desert

Larger but still dehydrated oyster mushrooms.  These mushrooms are rock solid due to the dry desert air.

Growing mushrooms in the desert can be quite a challenge.  Between the heat and the dryness it can seem nearly impossible.  I have been trying to grow oyster mushrooms here in the Sonoran Desert for quite sometime now without much success.  The first and primary problem is simply the lack of humidity. Before you ever get mushrooms to form, you must first colonize some sort of substrate with mushroom mycelium.  Mycelium is sort of like the "roots" of the mushroom. I have found it nearly impossible to colonize compost bins with mycelium simply due to the lack of humidity.  However, a more enclosed compost bin that traps moisture better may help, but also may make the process of composting more difficult.  Growing mycelium in quart or larger sized ziplock bags has worked extremely well though being the bags trap most of the moisture.  Growing mycelium though is the easy part. 

A few elm oyster mushrooms grown in the enclosed chambers described below.

Getting fruiting bodies, that is mushrooms, is extremely difficult through.  Nearly from the day tiny baby mushrooms form they begin to dry out and there growth is stunted.  I have grown many tiny mushrooms that dehydrate in the dry desert air before they are more than an inch tall.  I have found that soaking mycelium in water for 24 hours prior growing mushrooms helps, but the mushrooms still dehydrate after a short period of time.  They do get a lot bigger than the non-soaked mycelium mushrooms but still not more than two inches.  Putting the mushrooms in an enclosed container where the humidity is elevated also helps but creates its own set of problems.  In enclosed containers the mushroom mycelium can quickly consume most of the oxygen.  Mushrooms don't form well with low oxygen levels and form weird mutant looking stalks.  To over come the low oxygen levels I drilled holes in the side of the enclosed container and this has allowed for the most success.  Holes in the side of the container lower the humidity levels though, again causing dehydration problems.  So I have had to work to balance humidity levels and oxygen. 

The enclosed chamber we use to elevate humidity levels for growing mushrooms.

My current set-up is a large clear plastic bin with holes about every two inches on two sides and the top.  The bottom of the container is filled with perilite that is soaked with water, this helps raise and maintain humidity levels.  The mycelium is in a plastic bag that sits on top of the perilite.  There is a three or so inch slit cut in the side of the mycelium bag for mushrooms to grow out.  About once a day I open the container and spray it down good with some water.  So far it appears to be working.