A:  Open gallon zipper bag of dry casing layer material.  Pour 2 cups of warm water over the dry mixture massaging the bag as you go.  Evenly incorporate the water leaving no dry spots or clumps.  Add additional 2 cups of warm water in the same manner for a total of 4 cups of warm water.  Close the bag and let sit for 2 hours or overnight.

B:  Lightly scratch the surface of your colonized substrate block.  (see demo video)  Remove a loose handful of substrate.  Add handful of substrate to damp casing in the gallon baggie.  Be certain that the substrate is evenly distributed through your casing material and that there are no clumps or dry spots.  Firmly press any loose substrate not used back into the substrate block.

At the end of the 5th day you will "flush" your kit.  Thus beginning the force fruiting of your kit.  This is the step in which you will set all the mushroom pins within your casing layer.  You get one chance at flushing and setting all the pins for your kit.  
While all the pins are set at this time, not all pins will develop into mushrooms.  This is to be expected.
There are four key elements to getting the best flush for your kit:  temperature, evaporation/air exchange, moisture/humidity and the big "shock" of fresh air as you open the kit liner releasing the CO² and allowing the fresh air to circulate over the surface.  

To "flush" your kit: 

  a) Make sure your ambient air/growing temperature of the space that the kit is situated in is between 63 and 68 degrees with 65 being optimal goal... not below 60 and not above 68 degrees.  (more on choosing the best location for your kit below)

  b) Open the plastic kit liner bag, pulling it up and over the upright tabs of the box (please watch video for demo).  Note:  The kit will remain open for the remainder of its life. 

  c)  Using your spray bottle water the surface of your kit with COLD water. 

  d)  Apply your Humidity Tent/Cloth as detailed below.  This will be used for the remainder of the kits life.

When you open the kit liner bag you are shocking the mycelium and sending it into a fight or flight response where it feels that it needs to fruit - reproduce - in order to survive.  By opening the bag you are allowing the CO² that had built up to escape and fresh cool air to flush over the surface of the casing which is colonized with mycelium.  Then you are spraying it with cool water which further triggers the response.  Please note:  You may see a white weblike structure on the top of our casing.  This is mushroom mycelium (NOT mold).  

After you have flushed and watered your kit on Day 5 you will cover your kit with your Humidity Tent/Cloth (see below) 

Check your kit in the morning and evening.  Use your log sheet to make any notes along the way.  Make sure to remoisten your humidity tent and water the surface of the casing.  Water daily (morning and evening).  Keeping your casing layer as moist as it was the day you applied it.

During the next 7-10 days you may notice that the white mycelium strands are beginning to gather together and thicken.  They become thicker and and thicker, eventually forming white dots which are your tiny infant mushroom pins.  The pins will form throughout the casing layer.  They may be more easily seen with a flashlight at an angle to the casing surface.  Being white, they appear to sparkle like diamonds at the dark surface.  

Be sure your kit is not exposed to direct sunlight as this could encourage a greenhouse warming affect of the kit or direct airflow (such as a heater or AC vent) as excess air damages mycelium, pins and mushrooms or could even discourage them from forming.  Indirect lighting and indirect airflow are not an issue.  A moist lightweight cotton cloth such as a flour sack towel or old t-shirt draped over the top of the upright box tabs will help create a humidity tent and buffer any excess airflow.  (see below to create your humidity tent)  

Imagine a forest full of lush vegetation on a spring or fall day.  It is not bright, sunny or dry... it is moist and dimly lit.  With light rustling breezes.  This is what your mushrooms would like.  

Some people use a basement and others a rarely used bathroom or even a closet with the door open.   If there is no airflow present a fan set on low moving air indirectly throughout the space is important to aid in proper airflow and evaporation.

We have test kits set up on our kitchen floor and have even used the kitchen counter or a chair in the corner.  Wherever you choose, be certain your kit is easily accessible so you don't forget to tend to it daily and kept at approximately 65 degrees F.

Create a Humidity Tent using a lightweight cotton cloth.  AKA:  Humidity Cloth 

To prevent direct airflow or too low of Rh (humidity) from stunting or killing your delicate mushroom pins you will need to utilize a humidity cloth.

A:  Dampen a lightweight material such as a flour sack towel or other lightweight cotton material such as an old t-shirt, muslin or quilting fabric.  Anything lightweight that can hold moisture will work nicely.  At the faucet, dampen and wring out the cloth so it is damp and not dripping wet.

B:  Place the box tabs in an upright position.  Pull the plastic kit liner up and over the tabs - Taunt.  This will hold the tabs stable and avoid dampness from penetrating the box.  At this point your box will stand 12" tall and take a 12" x 12" footprint.

C:  Drape the dampened lightweight cotton material over the upright box tabs.  Allow an approximately 1" space on opposite sides to remain open and allow for proper airflow.  This is your "vent".  It can be adjusted to allow for more or less evaporation via airflow when necessary.

D:  Keep your fabric damp.  Check morning and evening.  Remoisting as needed.

You will have your kit set up like this for the remainder of the growing and harvesting stages.  

Day 7 beings the "Growing" portion.  This is a time of patience as your kit develops pins and those pins develop into mushrooms.  (see log for approximate time table)

You are checking your kit and its humidity tent twice daily and making sure to keep the humidity tent damp and watering the kit so that the casing stays as damp as it was when it was first applied.

The pins closest to the surface of the casing begin to develop into mushrooms first.  Once they become the size of an eraser at the end of a pencil - stop watering/misting.  Do not water on mushrooms once they reach this size as it may result in brown spots on the mushrooms.  (unsightly, but typically can still cook and eat)

Your mushrooms will double in size every 24 hours!  

YES!!  Once you can tell that you have mushrooms they grow FAST!  

So, keep an eye on them so they don't get away from you.

Once your mushrooms have grown to the size you wish to harvest you may do so by "breaking" them from the bed.  Gently hold the cap - twist and tilt leaving the casing layer beneath as undisturbed as possible so the pins inside have a chance to develop into mushrooms.  Trim and discard the end - tiny bit of casing and mycelium.  Harvest each individual mushroom as it is ready.  Each break may pick for 2-3 days.

Once your First Break is picked off, start to mist/water your kit again being certain to bring back the moisture level to what it was when you first applied the casing layer.  (do not drown or let the casing dry out as either of these could kill pins)

Mist/water daily (or twice daily depending on how dry the climate is) for the next 3-4 days or until the next break of mushrooms becomes the size of an eraser at the end of your pencil.  Halt watering when the size of a pencil eraser and allow the Second Break to grow to the size you wish and pick just as you did before.  

Once you have harvested your Second Break you begin to water again until the next break of mushrooms is pencil eraser size.  Halt watering while you observe them growing.  Harvest as before and repeat.  

Basic rule of thumb is that there is 7-10 days between breaks. 

and repeat.

It is normal for it to take a bit longer for the kit to bounce back between breaks as it progresses.  Meaning that between the first and second break the time will likely be shorter than between a third and fourth break.  Also, the quantity and size of the mushrooms will deminish as the kit matures and the mycelium begins to run out of food.  There is no way to "add" food.  For this reason commercial mushroom farms like ours are continually starting new crops and adding them to their system.  Removing the older crops when they are finished with their third or subsequent breaks to make room for fresh crops.  This method is similar to successive planting of corn and bush beans so there isn't a lull in harvesting.  Each crop overlaps the other and we are able to continually supply our customers with the same quantity of mushrooms. 

When a crop is finished producing we remove it to our outdoor "spent" compost pile where we then mix and bag it to be used in our gardens or sold to others to use in theirs.  Mushroom compost makes wonderful food for all sorts of plants from tiny veggie garden seedlings to giant trees.  Even house plants enjoy the food it provides them.  Plants Love it!

This video will show how and explain what you are doing when you "flush" your kit.  You will also be taken through creating a humidity cloth/tent.

Interested in seeing how we grow mushroom at our farm?  This video is a slideshow that I made years ago.    
While we still do have chickens, turkeys and ducks... we have made some changes to our formula and no longer utilize manure of any kind.  We utilize an all vegetable based composting system that Bob developed.  

This video has photos in it that may help you visualize what you are going to see happen as your kit goes through its various phases and give you a better understanding of growing agaricus mushrooms.  So, even though it is 'old'... I find it may be helpful.  

Hope you enjoy!  Happy Mushrooming!

This video demonstrates how to pick the mushrooms from your kit. 

It also discusses the humidity cloth/tent again.

In the store we see button mushrooms being picked when they are tightly closed and immature.  This is done mainly so they can withstand shipping and handling between distribution centers and grocery stores.

While the brown agaricus, Portabella/Crimini/Baby Bella which all the same mushroom - are picked at different points of maturity and/or size.  The label helps customers know the size and maturity of the same brown capped agaricus mushroom. 

At our farm we differentiate using three main labels:   1)  Crimini which are picked as the immature form - prior to opening.  2)  Once they are open and any size up to 3" they are called Baby Bella or Portabellini.  3)  Over 3" and we pack them as Portabella.  

Now for how to tell when they are ready.  To check your mushrooms prior to actually picking them just cup your fingertips under the cap to feel the underside.  There are several stages to feel for.  The first is "tight"  this is when the mushroom cap is still tightly holding onto the stem of the mushroom.  the veil is not exposed yet and therefore the gills are not.
The second stage is the stretching of the veil.  Feel under the cap.  If you feel a thin membrane and it is stretching and not open - this is the perfect time to pick the white button or crimini mushroom.  They are mature and flavorful enough yet not yet open and getting ready to drop their spores.  I find that the white button at this stage is quite a bit more flavorful than if you pick them tight and immature.  

The next stage of the Button Mushrooms is when the veil is cracked and opening.  This stage is acceptable yet for white buttons but we tend to send these particular button mushrooms to our restaurant accounts or keep them for ourselves as the shelf life is diminished somewhat and people prefer the 'look' of the closed mushroom.

  

If they are the brown capped mushrooms from cracked to open, they can go to both stores as prepack or bulk and restaurants.  If we package them for stores it depends on the size as to if they will have a Baby Bella or Portabella label put on them.  

Once a mushroom is open they will no longer "size".  They just "unfurl" and look like they are growing until the caps are completely flat and then they begin to release their spores.  You want to catch them before they begin to release their dusting of dark brown spores if possible.  A nicely cupped cap is the perfect time to pick.  As shown in the photos to the side.

If you happen to let them go too long and the brown spores are releasing all over your mushrooms all you need to do is rinse them.  If, when you go to pick your mushrooms you note that they look like little umbrellas that have gotten caught into the wind -we call this umbrellaing.

If at any time you see that the gills are black and glossy or the cap itself is slimy... they are way over ripe and should be discarded. 

If the gills are a pretty rosewood color and matte finish as shown in the photos... the mushroom is fine to eat no matter the stage of the cap, from closed to 'umbrellaing'.   Bon Appetit!

Spawn - Agaricus mushrooms do not grow from seeds.  They grow from mycelium that has been grown through a material such as sterilized millet or rye grain by a commercial spawn maker.  The spawn (specific for a certain strain of button or portabella mushroom) is added to the straw based substrate that is created specifically for the mushroom  mycelium.
Plase I & II Composting - The scienticfic smelly and labor intensive process to create the growing medium for agaricus mushrooms takes approximately one month.  During which time, the food for the mushroom mycelium is grown on the specially composted straw based substrate.  Our unique composting formula and process does not use animal bi-products or wood based materials.  During Phase II (the final approximately 10 days of the composting process which takes place in a special tunnel) the substrate is pasteurized and then slowly brought down through several temperature parameters to encourage the food for the mushroom mycelium to grow on the substrate.  Once the substrate is cooled to a certain temperature we then spawn the crop.  

Spawning - The spawn is then mixed in.  Spawn Run - Over the following ten days the mycelium jumps from the grain to the substrate happily eating and storing energy.  The process takes place indoors in a special climate controlled room called the "spawn run room".  All operations from this point on take place indoors in a special climate controlled space. 
Colonized Substrate - Mushroom mycelium is running throughout the growing medium happily eating the food source that was grown on the medium for it.  Fully colonized  substrate will have a gray or white appearance to it which may appear weblike.  This is mycelium running. Mushrooms are a fungus.  For this reason, mycelium looks similar to mold.
CAC - (Compost added at casing) A small amount of colonized substrate that is pulled from the growing tray and added to the casing material.  (In your case, the handful of material you scratched from the top of the substrate block to  mix with the casing material in the baggie.)  This is added to the casing layer to help encourage the mycelium to colonize the casing layer quickly.  If not added it will grow through, just a bit slower and you would want to wait a couple additional days before flushing.
Casing Layer - The moist layer of inert material applied to the colonized substrate block.  The mycelium will go on a mad search for food, finding none within this layer.  During its effort the mycelium will colonized the casing layer.
Casing is the operation where you apply the casing layer to the colonized substrate block.  Case Hold is the five days when the specially climate controlled 'casing room' is closed up to allow CO² to build within.  The room becomes warm and muggy - difficult to breath within.  You mimic this within the space between the casing and closed bag/substrate liner by closing it up after applying the casing material. 
Flush - On day 5 or 6 we note that the mycelium has colonized the casing layer.  The vents for the room are opened (you open your kit liner and leave it open) to allow the CO² to "flush" out of the room and the cold fresh air to "flush" into the room and over the surface of the growing trays (your kit surface).  At this time we water/mist the surface of the casing with cold water.  This process sends a message to the mushroom mycelium that if it doesn't fruit (reproduce) it will die.  A fight or flight responce takes place and the mushroom mycelium begins to gather together.  Pinning - The mycelium strands thicken as they gather together and over the next two weeks become mushroom pins (infant mushrooms).  All mushroom pins will develop within the casing layer.  It is important to keep the casing as moist as it was when applied as this is the sole source of water for the mushrooms.  It is important to maintain a growing ambient air temperature of 63-68 degree F as temperature is a major componet in encouraging the mycelium to fruit - reproduce.  If above 68 the mycelium feels all warm and comfy and sees no need to fruit.  Please understand, we do not make the rules.  The mushroom mycelium has its own set of rules here.  If the temperature is above 68 (even if it is just 70 degrees), it will not feel the need to reproduce, but it will continue to consume the finite supply of food that was grown on the substrate for it.  If below 63 degrees, things will slow down to a crawl and can possibly come to a near stop as matabolism of the food source decreases.  Optimal mushroom growing temperature is 65 degrees F with a range of 63-68 degrees F working well.
Break - The term used to decribe picking/harvesting.  Three (or more) consecutive breaks come every 7-10 days over approximately a months time.

Creepy Cawlies happen.  Every crop has its pest.  Mushrooms are no exception.  for them it is fungus gnats.  Fungus gnats seek mushroom mycelium.  They are quite attracted to the smell and will go to great lengths to get to it.  There are a few things you can do when you see adult fungus gnats on your kit. 

The best method of contact is through our email.  ShroomShack@gmail.com  Please feel free to contact us.  There are no dumb questions.  We are happy to hear from you and help you if the need arises.

Receiving, Starting and Casing your kit

Flushing your kit

Humidity Cloth Placement

Harvesting your mushrooms

Instructional Videos for the Agaricus Mushroom Growing Kits

Flushing your kit

Building a Grow chamber for your kit
Typically only necessary to create a perfect micro environment for your kit during the hot summer months or if you live in a warm climate.