Growing Mushrooms: PF Tek




About: Twitter: @mindsforge
This instructable will go over one of the most basic grow techniques (PF Tek) for growing a wide variety of mushrooms including Shaggy Mane, Lion's Mane, and P. Cubensis.

Video of some time lapses that I've done

Step 1: Supplies to Begin

To begin growing your own mushrooms you will need the following for the PF tek:

-Pressure cooker
Check thrift stores such as savers and goodwill, also browse your local listings for a cheap pressure cooker, my 8 quart set me back $50, the single most expensive peice of equipment to begin growing.

-Organic brown rice flour
I found the rice flour at Sprout's grocery, any health food or organic food store should sell this.

Found at nurseries, skip the big home improvement stores

I found perlite at Home Depot, but this can also be picked up with the vermiculite at a nursery

-Canning jars (Ive seen 1/2 pint used alot, as well as 8oz and 250mL jars)
Safeway, but any department store, even craft stores. Be sure to use wide mouthed tapered jars! To find out why check step 11

-Spore Syringe
Can be found online, or local shops, depending on species that you wish to grow

-Aquarium/Terrarium/Large tupperware (for humidity chamber)
I found a nice medium sized aquarium for $9 at a thrift store

-Hammer and Nail

-Aluminum foil

- Alcohol lamp or lighter

Step 2: Preparing Your Jars for Spore Syringes

Spore syringes are the easiest way to get started growing mushrooms with this technique. They can be ordered online from a variety of sources.

To prepare your jars, you will need a hammer and nail.

Remove the jar lid and lay the flat lid rubber side up on a table. Take a nail and make 2 - 4 holes evenly spaced around the edge.

NOTE: In the pictures I put holes through the jar lids facing the wrong way ... with the rubber side down. The sharp edge around the hole can tear the foil in the next few steps.

Step 3: Mix the Substrate

The substrate is what the fungus will feed off of. It will consist of brown rice flour, vermiculite and water. First, take the dry ingredients and mix them in a bowl. After they are well mixed add the water.

For 12x 250mL (~8oz):

-9 cups vermiculite
-3 cups brown rice flour
-3 cups water

For my mixing bowl I halfed the amounts above and mixed only half the substrate at a time.

I have heard of adding 'worm castings' (earthworm poop) to substrate to give better flushes of mushrooms.

Step 4: Fill the Jars

Once your substrate is well mixed and moist, begin filling your prepared jars with the substrate. Don't pack the mixture down, just loosely fill the jar.

Leave about 1/2 inch of space between the substrate and the top of the jar. I just filled my jars up to the threading for the lid.

Be sure to wipe up any moisture/substrate on the 1/2" inside and outside the jar.

Fill the rest of the jar with dry vermiculite. This is to make a barrier between the substrate and contaminants in the air.

Step 5: Get Your Jars Ready for Sterilizing

Now close up all your jars, with the rubberside facing upwards (upside down from how they were designed)
Place a square of foil over the lid covering the holes and sealing the jar from contaminants in the air. Crumple it down nice and tight, forming it around the jar lid.

Put about 3 inches of water in your pressure cooker and place as many jars as you can, stacking them if you have to.

I had no problem putting jars directly on the bottom of the cooker, but I have seen people put old canning jar rings in the bottom to help prevent jars from cracking.

READ your pressure cooker's manual if you have it! It can be a dangerous tool if improperly used.

Step 6: Sterilization

Close up your cooker and put it on a stove. I used a BBQ side stove to keep heat out of the house.

Start the stove up and wait until the pressure regulator (the ball/weight on top of the cooker) starts shaking. This is around 11-15psi depending on the manufacturer.

Let the jars and substrate sterilize for about an hour.

Once the hour is up, let the cooker stand for about 3 hours to cool down, you can also sterilize in the evening and let it cool down overnight.

Step 7: Inoculation

Inoculation is the process of introducing spores of your chosing into the sterilized substrate to take hold and grow.

In this step, be sure to take precautions to prevent contamination of the jars!!

Leave the jars in the pressure cooker until you are ready to Inoculate.

It is best to use a cleaned small room (such as a bathroom), HEPA flow hood or glove box when Inoculating.

Here is the basic order of things during the Inoculation procedure:

1. Open the pressure cooker
2. Remove a jar
3. Heat the syringe needle until it is red hot, with either a lighter or alcohol lamp
4. Remove the foil
5. Insert the needle into the hole you punched with a nail earlier
6. Inject some (about 1ml or so) of the spore saturated fluid into the substrate, on the wall of the glass jar. You should be able to see the needle tip and the water run down the side of the jar.
7. Repeat with the other nail holes
8. Replace the foil and continue with the next jar, reheat the needle if it touches anything unsterilized or every 3 or so jars to prevent contaminations.

See the second picture on this step for an example of contamination, green penicillium mold is a common contaminant. Yellow and pink discoloration is another sign of contamination.

Step 8: Incubation

Now that the hard part is over, you just need to let the jars rest somewhere warm and dark. Like in a cupboard above the refridgerator, or in a cardboard box by your computer tower.

This allows the spores to incubate into mycelium the body that absorbs nutrients and water.

Keep them around 80-86 degrees F. It will just take longer for the mycelium to grow if it isn't near the optimum temperature.

It takes around 3 to 4 days to see the first hairs of mycelium forming as white spots and 3 to 5 weeks to let the fungus get to a 100% foothold in all the substrate, depending on temperature conditions.

Step 9: Science: Mycelium

Mushrooms are part of the basidiomycota phylum which reproduce using spores (basidiospores) created on the gills (basidia) of the mushroom.

Hyphae is the stringy organic material making up the mycelium. When hyphae from 2 different mycelium bodies meet they share genetic material and create a dikaryotic, secondary mycelium structure from which the fruit bodies (basidiocarps) form.

That is why we inject spores in multiple places to create more than 1 mycelium body!

The following pictures show progress of the growth.

Step 10: Fruiting Chamber

A simple fruiting chamber can be fashioned out of an aquarium or a large tupperware box.

The main purpose of the chamber is to create a high humidity (90% to 100%) environment for our mushrooms to flourish.

To easily humidify the chamber, fill a strainer with your perlite and soak it in a bowl of water for 5 to 10 minutes, drain it, and line the bottom of the container with it. This will allow the water to slowly evaporate to create high humidity.

Place squares of aluminum foil where you will be putting your substrate cakes in the next step.

Be sure to use some sort of cover to keep the humidity in the chamber. If you can drill holes into the sides of the container to allow air exchange, the mushrooms produce CO2 and require O2 to live!

Step 11: Birthing Your Cakes

Once the mycelium has taken a hold over all the substrate in the jar, the next step would be to pop the colonized cake out, or birth it.

Birthing is a fairly simple process of taking the foil and lid off the jar, flipping it upside down on a paper plate or peice of foil and giving it a few smacks downward to dislodge it.

After birthing it is a good idea to soak the cake in water for about 24 hours. Temperature shocking the fungus by soaking it in the refrigerator causes the fruits to appear quicker than a room temperature soak.

I have also seen methods that roll the cake in dry vermiculite after they have been soaked and birthed.

Remember that mushrooms are 80 to 90% water!

Step 12: Wait for Your First Flush

It takes about 2 weeks for the first flush to complete growing depending on the species.

The cakes should last for about 3 or 4 flushes, in which you may "dunk" the cakes for 24 hours between flushes to rehydrate it.

If you plan on picking the mushrooms, just grab them from the base with your forefinger and thumb and break it off at the base. They can either be cooked fresh, freeze dried or air dried for cooking later!

Good luck!



    • Fandom Contest

      Fandom Contest
    • Growing Beyond Earth Maker Contest

      Growing Beyond Earth Maker Contest
    • 1 Hour Challenge

      1 Hour Challenge

    108 Discussions


    2 years ago

    Is it okay to use jars with metal lids? My local store doesn't have two parts lids

    3 replies

    Reply 7 months ago

    Two-player Lids are sold in every goddamn store on the planet


    9 months ago on Step 3

    I couldn't, for the life of me, find brown rice flour. So I put brown rice in a blender - super dry - and made myself some rice flour. Worked fine.


    9 months ago on Step 6

    Greetings Fellow Mycologist! I only have a small pressure cooker. So, just for the heck of it, I boiled half of my jars for 2 hours. Some say an hour and a half is okay too. No difference, so I've decided to skip the pressure cooker.


    Question 1 year ago on Step 12

    I'm not sure about this step any more information you can give me on Flushing


    1 year ago

    I am a beginner, I followed instructions, I received spore in syringes, it was pinkish in color. I inoculated the cakes and have been waiting , I had a look a few minutes ago and the jars are still pretty quiet, however one jar has myecelium but it is a very light pinkish color - is that because it is contaminated ? - any thoughts?


    1 year ago

    Hi I was wondering, when the mycilia is growing in the substrate do you need to mist it to keep it damp?


    2 years ago

    Hi everyone,
    the jars i'm using are 1 year old, and the growth of the mycelium is very different in the three jars (one is almost complete, the other two just started).
    Is possible that after 1 year the water inside the jars has gone? Can I add more water now? Thanks


    3 years ago

    Help! I can't tell if this cake is contaminated, this is my first time trying to grow shrooms and I'm just not sure.

    2 replies

    Reply 3 years ago

    toss it quick before it contaminates the rest of the cakes


    Reply 3 years ago

    i would say so I've seen cakes like that that didnt end up making it


    3 years ago

    I forgot to mention 200 ml of tap water is added too.


    3 years ago

    1 mole per L to zero moles HCl. Hydrochloric acid slowly evaporated outside. I did this also in a clean environment with 1 mole HCl. Normally after a week away from light and impurities no change in pH ( the ph was 1).

    So I know that metals would work to be Bio remediated this way too since they are water soluble.


    3 years ago

    A bit off topic but I am using Penicillium. D which I isolated carefully on mold from a lemon. I am using the fungi to absorb toxins and trap them into the spores themselves. These toxins are gold, copper and nickel.

    Once in my lab I had 1 mole of HCl measured plus pepsin with a pH meter. After a week this mold that I described above started to grow even though the pepsin will SOAKED in Hydrochloric acid. I measured the pH with paper and it was neutral. This fungi neutralized the acid!!!!!

    P. digitalium mold.jpg

    3 years ago

    Here is a picture of the done project.

    garlic + bleach.jpg

    3 years ago

    I have discovered that if you boil a 1.2-1.5% aqueous solution of sodium dichloroisocyanurate with fresh garlic bulbs there MAY an advantage to adding both due to several reasons. Garlic is a stable compound if it is placed into medium like agar agar. The bleach with garlic is sterilizing and preventing the growth of potentially dangerous mold.

    I was doing a project and I left garlic out and to my surprise no mold grew on it. There is naturally mold down there and if I could kill two birds with one stone all the better for the results.

    I am testing that theory right now.


    3 years ago

    A 0.1% solution of sodium dichloroisocyanurate is less corrosive because it produces lye, organic cyuranic acid which lowers the ph from 10- 11 to 7-8. As all plants and fungi cannot survive ph 10- 11 and even 9 is pushing it a bit is more ideal. This is comparison to regular bleach. Also bleach is unstable and will breakdown and provide less protection against the pathogens. Salts of sodium dichloroisocyanurate are more stable.