Growing Bulk: Part 2: Straw

This is the second part of a two part guide on how to grow your own mushrooms in bulk. You already have your halfway colonized jars from part 1. Now we’re going to grow on straw. In this part we’re actually growing the mushroom.

Step 1

I presume that you still have the materials from part 1 of this guide so this is what you need to buy for part 2:

1. Straw
2. 2 large containers to put your straw in (a rubbermaid for example)
3. Dish soap
4. Hydrated lime
5. A thermometer (up to 212°F)
6. Large plastic bags

Step 2

Cut your straw into small pieces between 1 and 3 inches and put it in the large container. Add boiling water until the straw is fully submerged. Add some dish soap. Mix it up real good and let it sit for 2 hours.

Step 3

Again boil some water and put it in the second container. Add 1 cup of hydrated lime for each 10 gallons of water. Now transfer the straw from the one container to the other.
Stick the thermometer in. Use some flat object  to submerge the straw completely (a plastic lid from a box will do fine). Temperature should stay between 90°F and 140°F for 1 hour.

Step 4

Take your jars and shake all the colonized grains lose. Hitting the jar against a bike tire or a roll of sticky tape helps, but be careful not to smash it.

Now take the plastic bags and open them up. Grab a hand of the straw, shake the excess water off and put it in the bag.
Then put some of the colonized birdseeds on top of the straw. Then again a layer of straw, and again a layer of seeds. Repeat this until your bag is filled. Make sure that the bag is filled tightly so press the straw together until it is packed together nicely. Make a knot in the bag so that it is tied shut. Now wipe the entire bag with rubbing alcohol.
Then you’re going to make a few holes in the bag for air exchange. Make sure the knife you’re using is rubbed with alcohol. The holes should be about 5 to 6 inches apart.

Step 5

Place the bag horizontally for about 2 weeks at room temperature until the fungus has fully colonized the straw.

Step 6

Once your bag is fully colonized it’s time to build your fruiting chamber.
Take one of the large containers and drill 1/4″ holes in it on all 6 sides, 6 or 7 inches apart. Then gently cut away the plastic bag with scissors careful not to damage the fungus mycelium. Place the straw log inside the container.
Place the container in a bright spot at room temperature. Mist some water inside the container to maintain high humidity levels. Be careful not to overdo your watering. You just need some condensation on the sides of your container.

Step 7

In about 2 weeks you should be ready to pick the fruits.
Below is an image of Psilocybe cubensis growing on straw.