Here's some data collected with a high-tech piece of machinery.
I thought THIS was something that would be of interest to people
contemplating mushroom cultivation using the perlite method. It is a
printout from a humidity/temp gauge, that I borrowed from the lab I work
at. it is an expensive and accurate piece of equipment called a
"hamster" and it records temp and humidity at preset intervals (30 sec,
1min, 1 hr) and stores these data points which are later read by a
I placed the hamster in a well sealed styrofoam cooler that had about
2" of perlite in the bottom and was filled with a weak H2O + H2O2
solution. the water solution was added until all the perlite had soaked
it up and there was no standing water pools under the perlite.
the hamster itself is approximately 4.5" long so the readings are for
the air 4.5" above the perlite layer. When you look at the graph you
can see that the hamster was placed in the cooler at about 1am on dec
4th and was not removed till after 9am the next day. the amazing thing
is the humidity was way over 90%. However, it is my belief that the
hamster is less accurate in the extreme humidity range, so I don't think
that the humidity was really the 97% that appears on the graph but I
would say it was at least 90%. There were NO cakes in this cooler, but
I intend to take more measurements with this thing once i have some
cakes to see if there is a difference. If all works well I intend to
share that data with everyone as well.