Growing Bulk: Part 1: Birdseed

So you’ve decided that you too can grow mushrooms. Well, GOOD FOR YOU! As you probably know mushrooms are good for your health and eating them can be so delicious! When they’re home grown, it just gives you that extra level of satisfaction. Now, let’s start growing!

This is the first part of a two part grow guide teaching you how to grow mushrooms in bulk (on straw).

Step 1

First of all, you’ll have to do some shopping. Go to your local supermarket and buy the following (if you haven’t got it yet):

1. Birdseed without sunflower seeds or corn
2. Tin foil
3. A cooking pot
4. A couple of pint glass jars with metal lids
5. Micropore tape
6. Rubbing alcohol
7. Latex gloves
8. Mouth mask

Also, buy a spore syringe online. Click here for a list of suppliers of edible mushrooms.

Step 2

Take your birdseed and soak it in hot water for 24 hours. Take out any floating seeds. Yes, every single floating seed has to be taken out. These often are hollow seeds and can contain contaminants. Next, put the birdseeds in a colander and let them drain until the seed shells look dry.
The seeds should still contain their moisture, but when put on a paper towel they can’t leave any wet spots.

Step 3

Now it’s time to take out your glass jars. Unscrew the lids and puncture 4 small holes in them using a nail and a hammer. The holes should be about half an inch from the side.
Grind down any metal that’s sticking out. You can seriously hurt your fingers with that.

Step 4

Fill the jars with the drained birdseeds. Leave about two inches of space from the top of the jar. Put the lids on. Stick micropore tape over the holes.  Wrap your lids and jars with tin foil. Make sure you don’t make any holes or tears in it, that is crucial.

Step 5

Put your jars in the cooking pot. Fill the cooking pot with water until the jars are halfway under. Put the water to a boil for about 2 hours with the lid on the pot. Make sure there’s always some water present in the cooking pot.
After this, take the jars out and let them cool down to room temperature. The simplest method is to leave them to cool over night. Remember that the inside of the jar is hotter than the outside. So it’s better to wait a bit longer. 12 hours should be sufficient. Leave the tinfoil on the jars!

Step 6

Take the rubbing alcohol and wipe your entire work area clean. Your work area should be under a flow hood. If this is impossible, work in a chamber where there’s no moving air or drag.

Take your jars into your work area, take the tinfoil off and rub the outside down with rubbing alcohol. Put on your latex gloves and mouth mask and rub your gloves with the alcohol. Now your completely sterile and ready to work.

Take the spore syringe you ordered online and hold the needle into a flame until it’s red hot. Then wipe it with some rubbing alcohol to completely sterilize and cool down. Now gently stick the needle inside one of the holes in the lid, through the micropore tape in one fluid motion. Tilt the syringe so that the needle touches the side of the jar. Gently insert 1cc of spore solution into the jar. Repeat this process for all holes of all jars.
Always take your needle through a flame and clean it with some rubbing alcohol in between two jars.

Step 7

Now place your jars somewhere where it’s not too bright. The jars should stay at a constant temperature. For most fungi room temperature should be fine. The jars should stay there for about 21 days. Until you see that the birdseed is fully colonized by the fungus.

Sadly, growing mushrooms on birdseed isn’t profitable, so we’re just using these colonized birdseeds to spawn (=fungi mycelium used to inoculate other substrates)  some straw in part 2 of this bulk grow guide.