3. CLEAN THE
This isn’t just Step 3; it’s something you’ll need to do every time you work inside your laminar flow hood.
The hood is crucial for mushroom growing, but it’s only one part of the larger regimen of cleanliness
required for successful lab work.
3a. Clean all of the hood’s surfaces with warm, soapy water.
3b. Disinfect all surfaces of the hood with a bleach-and-water solution.
3c. Finally, turn the fan on and disinfect the hood with isopropyl alcohol. You can never be too clean!
4. MAKE THE
We’ll begin growing our mushroom tissue in agar (seaweed gelatin), a standard laboratory growth medium.
Petri dishes are traditionally used, but you can use any shallow, washable container with a lid. As long as
you’re cooking a batch of agar, you’ll find it handy to make several of these plates at once and store them in
airtight bags for later use.
4a. Drill or cut a ½" hole in the lid of a washable plastic container.
4b. Wash the container and lid with soap and water, and then sterilize by immersing them in simmering
water for 3 minutes. Switch on your hood’s fan, and move the container and lid inside for drying.
4c. Make a filter by soaking a piece of
cotton or sponge in isopropyl alcohol
and then wringing it out. Place the
filter in the hole in the container lid.
It should fit snugly.
4d. Mix 1 tablespoon of agar in 1 cup
of water. Bring to a low boil and slowly
simmer for about 15 minutes, stirring
occasionally. Add a large pinch of the
growing substrate you’ll be using later
(sawdust, cat litter, barley, etc.) to the
simmering agar as a source of nutrition.
4e. Inside your hood, pour the hot
agar into the newly sterilized container
until it is about as thick as a pencil. Let
the gelatin cool and congeal.
The sponge-piece filter
keeps the mushroom tissue
protected while letting it
exchange gases with the