Introduction: Beginner's Guide to Growing Mushrooms

This guide is a step-by-step guide for beginners that want to grow mushrooms. I didn't come up with most of these techniques (actually, probably not any of them) and will cite sources when possible. I'm not trying to take credit for any of this, I'm only aggregating information to make things easier for people interested in growing since there is a lot of content out there, so I'm just going to simplify it down and show you what to do and when to do it. I recommend following this exactly for your first attempt, and if you feel like tweaking it then do so on your next grows.

Step 1: Gather Your Equipment

The easiest, cheapest, and most accessible method is the "popcorn tek" (see here for more info: You can also use rye berries or something else but let's just keep it simple and focus on the popcorn for this. To avoid confusion, this list is only for the jar / inoculation phase. More stuff will be listed in another step.

Here is what you'll need:

  • Pressure cooker
  • 1qt widemouth jars - (I like the widemouth ones, they have more room on the lid which you will want)
  • Scotch tape
  • Polyfill (the stuff in pillows - if you aren't near a fabric store or someone that has this, buy the cheapest $4 pillow at target and tear it open. It's probably cheaper that way anyway)
  • A big clear storage bin (for a still air box - more on this below)
  • A drill and hole saw (or some other way to cut big holes in your tub for your hands to fit through)
  • Latex gloves (not 100% necessary but can't hurt)
  • Rubbing alcohol
  • Strainer
  • Aluminum foil (get the stuff that says heavy duty if you can)
  • Hand sanitizer (maybe not necessary but to be clean!)
  • A lighter
  • Lysol Neutra Air
  • Some spore syringes
  • Optional but useful: An alcohol lamp

Step 2: Preparing the Jars

Once you have all your stuff, the first thing you'll want to do is soak 2 bags of the popcorn. Simply dump 2 bags in a big bowl, fill it up with water about 2" above the top of the popcorn and walk away for about 24 hours. 2 bags should fill up at least 7 jars, probably more.

Note: You will be filling your jars up approximately 2/3 full of the popcorn. Spore syringes are typically 12ml - each jar will need just 2ml, so that is enough for 6 jars. Obviously if you have 10ml syringes, it's enough for 5. If you want to start with just 1 syringe, you can probably use 1 bag of popcorn and split it evenly between 5 or 6 jars.

While you're soaking your popcorn

You can be getting your jar lids all setup. You can get real fancy with jar lids, but let's just not do that yet. You'll want to poke 2 holes in your lids, a large one in the center and a small one toward the edge. You can drill then or punch them with a screwdriver and a nail if you want but just be careful not to cut yourself, the edges are sharp!

The large hole in the center is for the polyfill, it allows a 'gas exchange' which basically means it lets CO2 escape the jar without letting contaminates come in. The small hole is to put your spore syringe through, so make it a bit bigger than the syringe needle but not too big. You will stuff the polyfill in the center hole and put a piece of scotch tape over the inoculation hole. There are teks on this out there if you have detailed questions on how to stuff that polyfill hole. Some people use micropore tape over this hole, I haven't done that so I can't say if it's any more or less successful but if you do use that, make sure you put a couple strips of it on because 1 strip seems too porous to me. Note in the picture of the jar lid, it's on upside down - we do this because we're not trying to seal this thing up like we're canning grandma's pears here.

24 hours later

Once your popcorn has soaked for 24 hours, dump it into a strainer and rinse it off real quick. Then put it in a pot, fill it up with fresh water to about 2" over the top of the popcorn and turn on your stove. (we are NOT pressure cooking this but you can use your pressure cooker if you don't have a large enough pot, but make sure the lid is off!) Bring the water to a boil. Once the water begins boiling, set a timer for 40 minutes. Make sure it stays at a nice low boil, nothing too crazy, and keep stirring it now and then to prevent any burning on the bottom of the pot.

After 40 minutes, check a couple corns by putting your finger nail in them to make sure it can somewhat easily dig in - you should be able to squish one between your fingers. When this is ready, turn off the stove and dump your wet hot popcorn into a strainer. Do not rinse it here, because as a friend told me its like taking dishes out of a hot dishwasher, the hotter it is the more the steam comes off and dries it up. I like to get my corns up around the edges of the strainer and mix them around with a metal spoon ever few minutes for about 15-20 minutes until they're basically dry to the touch. The goal here is not to get any excess water in the jars.

Now, start scooping popcorn into the jars, get them around 2/3 full - you want room on top so you can shake these jars later - don't overfill them. Close the lids upside down as shown in the picture.

Once all of your jars are ready to go, cover them with your heavy duty aluminum foil.

Step 3: Pressure Cooking & Work Area Prep

Hopefully you read the manual for your pressure cooker, don't take my advice on how to operate this thing. But now you'll want to add the minimum amount of water to operate it safely (there is probably a line inside) and put your foil-covered jars in. Depending on the size of your pressure cooker, you can fit probably up to 7 jars in at once. You CAN put a couple jars on top sideways.

Lock the lid on, do everything the manual says to do and then put it on the stove (or plug it in or whatevever you do with the one you have). Wait until the pressure gauge gets up to 15psi and start your timer for 50 minutes. Don't walk away from this thing, stay in the same room for the next 50 minutes and adjust the heat on your stove as necessary to keep it at 15 psi, it's pretty easy to do but just don't walk away from it. Maybe put on some headphones and listen to some Pink Floyd or something for the next 50 minutes, keeping an eye on that pressure gauge.

Once the 50 minutes are up, turn the heat off and walk away. DO NOT OPEN THE PRESSURE COOKER! I let this sit overnight personally, but a few hours will probably do as well. Of course, make sure there is 0 pressure and it's cooled down for a long time before you open it or you're going have a bad time. Also, you want the corns to be cooled way down so you don't inoculate them and burn up your spores because well then you've wasted a lot of time.

While your jars are cooling you might as well start preparing your work area.

Get your big clear tub and cut some big holes in it that you can fit your hands through and work in, this is going to be your still air box (there are teks out there for this if you need more instruction). The idea here is that when you inoculate, you do it inside this box where contaminates aren't blowing around. I use a big 5" hole saw for this, but if you don't have that, feel free to look up "still air box tek" or check google images for some examples.

Put some foil on top of your table or your work area for the heck of it, spray some of your lysol inside of your box, over the foil, and around the room. Sing "The Sound of Music" while you do this if it makes you feel good.

Step 4: Inoculate... Then Wait!

Once your jars are nice and cool, go ahead and gently spray around the area with Lysol again maybe 15-30 minutes before you start. Take a shower, put on some clean clothes and do your final preparations.

Put the following inside your still air box:

  • Scotch tape
  • Lighter
  • Your Jars (if you can fit them all in)

In a handy place outside of your still air box, have:

  • A folded up paper towel with rubbing alcohol on it.
  • Your syringe(s) with the caps still on
  • Gloves if you have them
  • Hand sanitizer

Now I get a little extra clean here, it might not be necessary but I would rather be safe than get contams. What I like to do is: Wipe my hands and wrists with hand sanitizer, let it dry a bit and put on the gloves. Then I reach in and pull the foil off of the tops of the jars and take it out of the box. Next, I do a quick wipe over the scotch tape'd inoculation area with the rubbing alcohol, and I take the paper towel with the alcohol out (so it doesn't get all flammable in there when we use the lighter). I then remove the gloves. I now have a pile of garbage next to me, outside of the still air box, containing foil, an alcohol soaked paper towel and a pair of gloves.

Now put on a fresh pair of gloves and grab your syringe. Shake the hell out of it hard and fast for a minute or so, get the spores all spread out in the liquid, make sure there are no clumps.

Put your hands inside the still air box and remove the cap on the syringe. Light lighter, hold it under the needle until it is red hot. Let the needle cool off a few seconds until its no longer red and puncture the scotch tape on your first jar. Aim the needle toward the side of the jar, so the spores/liquid spray against the glass and run down into the popcorn. Use only 2ml of liquid from the syringe. Remove the syringe and quickly put a piece of scotch tape over the hole you just punctured. Move that jar to the other side of the clean air box.

Now, light the lighter and get the needle red-hot again. You will do this every time between every jar, to prevent any possible cross contamination between jars. Repeat until all of your jars are complete.

Once all jars are complete, remove them from your still air box and put them up in a closet or something, I put the jars back in the box they came in personally and put a towel on top. Ideally you want to keep these at around 73 degrees farenheit but anywhere between 70 and 86 is probably ok, some people say its good to have it in the 80s and others say it makes it more susceptible to contamination. I do know low-mid 70s works fine.

Now go put all your crap away and wait! You should see mycelium forming somewhere in 5-10 days. If it comes early, welcome it. If nothing is happening in 10 days wait til 14 or so, maybe more. But usually within a week you'll see something.

Step 5: Shake Em Up... and Wait Some More!

If you're anything like me, you eagerly inspect your jars daily. Look for contamination. If there is green stuff, bag the jar up and throw it out. Take the financial hit and don't open it and let those nasty green spores out, just toss it. This happens from time to time, don't get discouraged if a jar or 2 get contams, instead be happy about the jars that are not contaminated! There are other types of contams, so do some research on this especially if you see anything not white in there.

Once the jar is around 70% full of mycelium, shake it up. Shake side to side, bang the jar against something (some say use a car tire) try not to shake it up and down, we don't want the corns to hit the polyfill if we can avoid it. Once everything is all shaken, your jar will look a little sad but don't worry just put it back where you found it and wait a couple days - your mycelium will be spreading faster and better.

Wait until the jar is 100% colonized by mycelium and then... Wait 5 more days! Yep, wait 5 more days to make sure all of the corns in the middle that you can't see get colonized as well. But don't worry, we have stuff to do during this 5 days to prepare for the next stage!

Step 6: Prepare Your Monotub(s)

This tek has worked perfectly for me: and that's what we'll be doing.

Time to do some shopping, you'll need:

  • A couple tubs depending on how many jars of corn you have. (If you have 4 or 5 jars you can use 1 tub, somewhere around the 66 or 70qt. If you have more, you can split it into 2. I have used various sizes and personally I prefer clear ones so I can check on them without opening them. Let's assume you have 4 or 5 jars right now)
  • Some coir bricks
  • Some vermiculite (the fine stuff not the chunky junk - go to your local hardware store and get a giant bag of this to keep around.)
  • Some big trash bags
  • Micropore tape
  • Polyfill (you should still have)
  • Drill - around 1" +/- (or a knife to cut some holes)
  • Scissors or a sharp razor
  • Latex gloves (for the hell of it)
  • A 5 gallon bucket with a lid
  • A thermometer (a cooking/candy type is perfect)
  • Temp/humidity monitor (pick one, doesn't have to be this one)

Preparing your tub(s)

Prepare your tub(s) by drilling 1 hole on each side, in the center about 4" from the bottom.

Tape over the holes with your micropore tape, I use 3 pieces of tape here so its not allowing any fresh air in, but does let CO2 out. (you may be able to just use regular tape over these holes at this stage, I have some tubs where I didn't have any holes in them yet and they worked fine)

Step 7: Prepare Your Substrate

Once your popcorns are 100% covered with mycelium (+5 days) it's time to add them to the tub. Again, we are using this tek so read it, I'm giving an abbreviated version here.

Pasteurize your substrate

Take one of your empty 1qt jars (if you have any around) and use it like a measuring cup, put 4 quarts of water in a pot and put it on the stove. While that's happening, open your coir bricks and drop one into the 5 gallon bucket.

Using your 1qt measuring system, scoop up 2 quarts of vermiculite and put that in the bucket as well (see tek).

Once the water comes to a boil, carefully remove it from the stove (you're a grown up you know how to do this safely I hope) and pour it in the 5 gallon tub over the top of the brick of coir and vermiculite. Put the lid on top of the bucket and walk away for about 30 minutes.

30 minutes later, open the bucket and stir around the now-swollen up coir/vermiculite - I use a big metal kitchen spoon for this and I like to be wearing latex gloves for good measure. Just make sure any chunks of coir get broken up, and close it back up for another 3 or 4 hours.

After 3-4 hours open up your bucket and check the temperature with your candy thermometer. If it's over 80 degrees Fahrenheit, put the lid back on and wait another couple hours.

Once the coir/verm mix is 80 degress or less, we are ready to transfer the popcorn into the tubs.

Step 8: It Puts the Corns in the Tub

Assuming you have 4-5 jars of mycelium-coated popcorns: Wash your hands, put on your gloves and dump the entire contents of your 5 gallon bucket into a large trash bag. Now, open up your jars 1 by 1 and dump the corns into the bag with the substrate.

Once all of your corns are emptied into the bag, gently shake it around and kind of 'kneed' the bag from the outside - just mix the corns into the coir.

Next, cut the bag down a bit so it's just a few inches above the coir / popcorn mix and place the bag inside the tub. At this point, I like to trim up the edges so the bag is below the air holes (remember the holes are still taped up, we do not want fresh air in this thing yet) You can tape the bag up along the sides if you want, I don't do this but you can if you want.

Wedge the thermometer/humidity gauge in there somewhere, put the lid on the tub and go put it away in a dark closet. I keep it at the same temperature as I kept the jars, somewhere in the low-mid 70s. Now you wait again, for another 7-10 days.

If your tub is clear you can peek inside a bit - the sides of the tub should be wet from the humidity - you should basically see the dark coir becoming more and more consumed by mycelium.

Step 9: Get a Little Fresh Air

After 7-10 days you should have a tub pretty much full of mycelium and its time to start introducing fresh air (people call this FAE: Fresh Air Exchange). There are all kinds of opinions and teks out there for this, I'm going to tell you what I have seen work.

At this point, remove the tape from the holes and fill them loosely with polyfill. Leave the tub(s) out in a room that has some natural light in it, there is no reason to get crazy here with lighting just put them out in a room somewhere that has a window in it if you can.

Use a timer like this to turn on a fan 3x a day. For example 8am for 30 minutes, 12pm for 30 minutes, and 7pm for 60 minutes. Don't put the fan super close, just have it on in the room. The goal is to introduce fresh air, get rid of the CO2, yet keep the humidity that the coir/vermiculite continues to provide in the tub. Check your humidity meter and make sure it is over 92%. It may go down into the 80% - 85% while the fan is on, that's actually perfect and when the fan turns off it should go back up in a couple hours to 95%+

If your humidity gets low (and stays low) you can mist the tub, but you shouldn't have to do that if everything is setup properly.

So now we wait again for another 7-10 days.

Step 10: The Fruits of Your Labor

After about a week you will probably see some primordia forming in your bin, it's like little tiny white balls on/in your mycelium, these are going to turn to pins. A couple days later you'll see your first pins which will soon grow into big adult mushrooms.