Casing Overview

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By Admin (Admin) on Thursday, August 23, 2001 - 11:54 am:


There are many Casing Teks. You should Pasteurize or Sterilize your casing. But they all have the same purpose of wicking liquid water to the substrate.

All of these teks can be used. You can also substitute straight Vermiculite (verm) with or without a pinch of lime in any of the following:

50/50 & 50/50+

Hongus' Tek

Mushmush Casing Tek

Karl's Pie Pan Tek

9er Tek

3M's Dung Tek or (OGBD)

Shroom Wizard's Casing Tek

You may also want to look at Flat Cakes, and if you cannot obtain Verm look at Coco or "Coir" Casing.


Basic 50/50+ Casing Mix


Peat Moss
Crushed Oyster Shell
Hydrated Lime
Bottled Water

Basic Procedure:

Mix together equal parts of vermiculite and peat moss to create a 50/50 mixture of both. Add 15% crushed oyster shells and 8% hydrated lime by volume, to the overall 50/50 mix. Then proceed to add this casing soil as usual. The lime acts as a buffering agent for the pH, and put contaminants behind. From The Hawk's Eye

Hongus' Way


one bag of horticultural vermiculite
one bag of Jiffy Mix


Mix three parts vermiculite to one part Jiffy Mix (3:1). Make it real moist but squeeze until it barely drips. The Jiffy Mix makes the soil very airy and the vermiculite retains the moisture.

MushMush Casing Mix

10 parts of peat
5 parts of vermiculite
2 parts of limestone (Marl)

The ingredients are mixed in dry form and while stirring water is added. The amount of water of course depends on the moisture content of the peat. The object is to get as much water in the casing soil as possible without turning it into mud. If the casing gets too wet just add a little more dry ingredients. This casing soil is then filled into oven bags (made of nylon), autoclave bags (PP) or jars and these are sterilized for one hour in the pressure cooker. When the soil has cooled down to room temperature it's ready to use.

Often an alternative method that utilizes the microwave oven can be used. The moistened casing soil is filled into heat resistant bags or jars and is sterilized for 20 minutes at maximum power in the microwave. Just add some extra water to make up for water loss from escaping steam.

3M's Dung Tek [see: OGBDLichen Tek]


1 5x9 aluminum bread pan
1 cup of colonized wheat
a pillow case full of well composted horse dung
a large pot of boiling water
a bread knife
a grow chamber


Step 1: place colonized grain in an aluminum bread pan and allow to sit in chamber until the grain knits together nicely(2 or 3 days). With this size of pan you get a layer about 1" thick.

Step 2: Bring pot of water to boil and submerge pillow case of crumbled horse dung in the hot water. Remove from heat. Allow it to steep for 45 minutes.

Step 3: Drain the dung and allow to cool overnight.

Step 4: Squeeze excess water from the dung with your fist and crumble it over the grain in the pan. Fill the pan to the lip with the crumble dung. Consider the dung as a casing. Place back in your chamber and keep humidity around 85-90%

Step 5: Initiate pinning when mycelium starts breaking through the surface.

Step 6: After you have harvested your flush remove the mycelium from the pan and gently hold it on it's side. You will see the line where the dung joins the grain. Carefully slice off the entire dung layer and recase with fresh dung. Repeat steps 1 to 6.

After the 5th flush remove the dung layer and crumble the grain into fresh dung filling the pan to about 1/2-1" below the edge and case with more dung. Post flush in this phase slice off the top 1" of your mycelium loaf and replace with fresh dung again.

"My record using this method is 9 flushes and 4 months before contams claimed the pan. You will find that your subsequent flushes are larger then you are used to since there is more nutrition available to the mushrooms then when using verm or peat based casings." - Mystic Mountain Mushrooms

Shroom Wizard's Casing Tek


potting soil
a spray bottle with water
plastic trays
large mixing bowl
substrate jars colonized with mycelia


In the mixing bowl, add 1-1/2 cups of potting soil and 1-1/2 cups of vermiculite. Mix these ingredients together using a large spoon until they are well combined. Using the spray bottle of plain water, lightly spray the mixture and mix with the large spoon several times until the mixture is moistened to field capacity, meaning that if you take a handful of this mixture in your hand and squeeze it into a ball it will hold its shape but no water will drip out. We want the mixture moist but not saturated.

Pour the soil/vermiculite/water mixture into one of the trays and spread it level on the bottom. Remove the lids from three of your substrate/mycelium jars and dump the contents on top of the soil mixture on the bottom of the tray. Using freshly washed hands, crumble the mycelium/substrate cakes into small pieces (about the size of marbles) and spread them out into an even layer on top of the soil/vermiculite layer.

Put 3 cups of plain potting soil into the mixing bowl. Using the spray water bottle and the large spoon, spray and mix back and forth until your soil as reached the field capacity stage(as described previously). Pour this into the tray on top of the crumbled mycelium/substrate cakes and spread level with the spoon. What you should have now is a three layer sandwich. Bottom layer being soil/vermiculite, center layer being crumbled up mycelium/substrate cakes and top layer being plain soil. Put the lid on the tray and repeat this process with your other jars and trays until you have all of your jars cased.

Proceed as usual.
From Shroom Wizard

Related Links: Troubleshooting Casings : Cakes or Casings? : Shroom Glossary

By onediadem (Onediadem) on Wednesday, November 14, 2001 - 03:09 pm:

My friend plans on using the flat cake method. She has read about using verm. only as a casing on top and bottom of pan. Does using vermic. only offer up good flushes? Or would you recomend the 50/50?
She is familiar with the whys, but is wondering which yeilds better? tnx
live long and prosper

By quote: (Quote) on Wednesday, November 14, 2001 - 05:14 pm:

long arguments have raged over that question.
yes, verm alone offers good flushes.
the addition of the peat in the 50/50 mix can give better results when it works right.
but peat is more prone to contaminate.
so it's a bit of a trade-off.
if contams are problematic in your environment, then go straight verm.
but if everything's clean and sterile, then the 50/50.
just be sure to balance the ph with lime, oyster shell, etc. and sift the peat 1st to remove any twigs.

By An guy (Boomer) on Wednesday, November 14, 2001 - 05:29 pm:

Can you use ground up eggshells to balance ph, do you know?

By quote: (Quote) on Wednesday, November 14, 2001 - 05:32 pm:

never tried it but i know eggshells are used in soil/compost and it takes quite awhile to break down. might be too slow to work in a casing.

By Nan (Nanook) on Wednesday, November 14, 2001 - 05:48 pm:

Eggshells work but they have to be cleaned (boiled or they contam) and crushed... And it takes a lot of them. Some beach sand is good, the kind made of crushed shells. Most people go with a mixture of Lime and crushed oyster shell.

By onediadem (Onediadem) on Friday, November 16, 2001 - 07:51 pm:

If I am to understand correctly, The casing layer offers no nutritional value, it is to keep moisture content up. If so, why would one use worm poo? Also, would a rubbermaid storage container with perlite in the bottom, reduce the need to mist? Would one just fan as normal and close the container? Or, stil mist after fanning? I am sort of confused at this point. Also wanted to let you all know, the karo tek is coming along famously. I will be inocculating Sun. nite. I also did the karo tek with pf and hawaiian today. Thx all.
P.s. Surgury is set for monday, say a little prayer for me.
Live long and prosper,

By Underground_Shaman (Shaman) on Friday, November 16, 2001 - 08:12 pm:

Yes, technically a casing is non-nutritive and for support, mostly for pinning. Those casing teks that have nutritive potential are more accurately considered a second substrate. The mycelia colonize the poo and extract nutrients...this will slow down the time from spawning to fruiting, but people use it because the extra nutrients can lead to GREAT flushes.

I wouldn't case with straight poo, it would be too dense. You want a light, airy casing with lots of microscopic air pockets. What method of spawning/fruiting are you planning to use? This will guide the decision on casing material.

Perlite can reduce the need to mist. The most important factor is the chamber's humidity, period. As long as the walls are dripping with moisture, you're fine. Experiment to find what works best for you. It also depends on whether we're talking cakes or cased spawn. Cakes need more ambient humidity than cased straw, for example.

Will be sending good karma your way all weekend, hoping all goes well.


By Brettiejams (Brettiejams) on Friday, November 16, 2001 - 08:49 pm:

Sound advice Shaman......

And, if I may intrude, I would like to offer my prayers to you Pam... I have enjoyed reading your posts recently and am delighted to have you amongst us here at The Nook.

Prayers and well wishes to you on your surgery

I hope you will have recovered enough by Thursday that you are able to enjoy your Thanksgiving.


By Nan (Nanook) on Friday, November 16, 2001 - 09:08 pm:

I second Bretti's well wishes

As to your questions... Casings with nutrient additives contam at a higher rate. You really have to have your shit down properly to avoid major contam problems... The organics cause pH changes in the casings as they age, and contams can rip right through enriched casings unless your Tek is good. I do not advise it for beginners.

In general I have learned the wisdom of scraping off the old casings between flushes, and I do this with Verm, 50/50, enriched casings, whatever. It helps keep the contams down and I get very nice second flushes on straw beds when the casing is 80% removed after harvest and clean, damp, casing is re-applied.

By onediadem (Onediadem) on Friday, November 16, 2001 - 09:38 pm:

Thank you all, I am still contemplating which method will work the best for my situation. I will be starting off with cakes, and probably go to cased rye grain, possibly straw. I had really awsome results with the mycellium screaming through the rye with no contams, but my teks after that were horrendous. Actually, the stuff I read before finding Nan's Nook was horrendous, and I didn't get the humidity thing at all. Before, I mixed pint jars of awsome fully ran rye, with straight worm poo, was told to pack it as tightly as possible, and just sat it in my dark closet, with a mist here and there. All I ever produced after mixing with the poo was mean greenies. I imagine, had I just cased the rye in a pan or something, and had it in a container with perlite, I would have had shrooms eventually. But, for now, I think I may do the pan tek with the cakes, then case. Thank you for the prayers and well wishes, I appreciate them tremendously.
L.L.A.P., pam

By quote: (Quote) on Saturday, November 17, 2001 - 01:00 pm:

i like to mix the castings with straw, which lightens the mixture considerably. then spawn it with rye.
and, btw, best wishes on your upcoming surgury.

By greenthumb (Greenthumb) on Saturday, November 17, 2001 - 02:14 pm:

Just relax and work on getting that neck right. I'm sure that combining your wonderful imagination with a few weeks of forced bed-rest will produce many "fruitful" casing ideas.
I'm sure you've heard this before, but once more won't hurt.

These procedures are done on a daily basis and with amazing rates of success.
Keep your spirits high.

Maybe after this your kids won't find you to be such a pain in the "neck"!!!! sorry

All the best-G

By wycrobro (Newman) on Wednesday, November 21, 2001 - 04:55 pm:

Hello I'v just gone through the mycroporn in the all the pics. the casing looks soooo covered im mycelium almost matted I tried to start fruiting mine when only some of the mycelium was showing through the casing .
Does anybody have pics with the right amount showing through, at time when you first put it under light , drop temp ect.

Tanks for the help

By quote: (Quote) on Wednesday, November 21, 2001 - 05:00 pm:


By quote: (Quote) on Wednesday, November 21, 2001 - 05:03 pm:


By Fishy1 (Fishy1) on Thursday, November 22, 2001 - 05:50 pm:

All of my Qt. jars are being used. Would it be ok to put a loaf sized "cake" of peat casing in the PC that is simply laid on HD foil, and wrapped up like a meatloaf, then wrapped again 2-3 times? I will put it in the PC supported on 4 empty jars.
Whaddaya think? fishy1

By nuecrew (Nue) on Thursday, November 22, 2001 - 06:29 pm:

I have a large American PC and I've put a pillow case 1/4 full of 50/50 in the PC @ 15 Lbs. for 45 min. several times with no problems. I did keep it off the bottom with an inverted plate on crumpled Al foil. Your loaf sounds like a safe thing to do.

By Nan (Nanook) on Thursday, November 22, 2001 - 06:37 pm:

I do it exactly the same way Nuecrew does, but your idea should work fine.

Straw Tek Tips : Sterilizing Casing

By Fishy1 (Fishy1) on Thursday, November 22, 2001 - 06:37 pm:

Well, its been in there 30 min now, and sounds fine.
Wow, a Thanksgiving feast....Peatloaf!

Shroom Glossary

By PsychoBass213 (Psychobass213) on Wednesday, December 05, 2001 - 01:50 am:

I've read a lot about casing and flat cakes and stuff but there's still something I'm wondering about since I can't easily get my hands on some of the things needed for some more complicated casing layer recipies.

What does the casing layer do besides give the substrate water and protect it from contams?

And how much different will my yields be if I just use plain vermiculite rather than dung or peat or whatever else? I'm just using crumbled/sliced cakes not grain or straw. Thanks!

By Trollhunter (Trollhunter) on Wednesday, December 05, 2001 - 03:11 am:

to protect the colonized substrate from drying out .to provide a humid microclimate for primodia formation and development .it provides much needed water to the shrooms . to provide the growth of fructification enhanceing microorganisms .but that is when you are useing shit for the last part .and as for yeild you will get more from shit , than from ver .

By quote: (Quote) on Wednesday, December 05, 2001 - 03:16 am:

you can get decent yields from plain vermiculite casings, no great need to bother with peat, etc.

By Snoopy (Snoopy) on Wednesday, December 05, 2001 - 03:26 am:

yepp...... plain old vermiculite works just fine.

Example altho blurry just because i find it so pretty. I am sure Eatyou has some nicer pics tho..

regular flatcake made in a bread pan, with 1 pfstyle halfpint cake
flat cake

By onediadem (Onediadem) on Wednesday, December 05, 2001 - 08:53 am:

Thank you Snoopy, that answered a pondered question of mine. I will be going to rye as a substrate, after the cakes I have going are done.
I just dont have the patience with the cakes. I am used to innoculating rye, and the colonization seems to be the speediest for me, and my situation. Plus, theres the added bonus of being able to shake the rye to distribute the growing mycellium, which you cannot do with the cakes. I am going nuts on waiting for these cakes to colonize. I have to smack my hands to keep from shaking them.
Twitching impatiently,

By nuecrew (Nue) on Wednesday, December 05, 2001 - 09:39 am:

This is very interesting for more reasons than one. Are you saying(Quote)that you could case 9er style with just moist sterile vermiculite?

By Nan (Nanook) on Wednesday, December 05, 2001 - 09:47 am:

I shoot quarts with polyfil lids. Karo syringes using 5-6 cc's per jar (I fill jars to the top and don't bother shaking). I insert the needle into the polyfil and tip the syringe, and jar, in order to get inoculum to run down the glass walls. Rotate the jar as you steadily inject at least 4 cc's of Karo Tek. The inoculum will cover a huge amount of area (and volume) because the grain does not absorb the liquid like verm does in the PF substrate. Once the jar is injected, shake it around to distribute and even out the inoculum.

You only have to shake the jar once... When you inoculate. I make the grain just a tad dry, and make sure 5-6 cc's gets splashed around plenty

By Nan (Nanook) on Wednesday, December 05, 2001 - 09:49 am:

Yeah, you can substitute straight verm for any casing recipe... As long as you are growing Cubies.

By An guy (Boomer) on Wednesday, December 05, 2001 - 09:49 am:

pppppppppj, quitcher twitchin.

and stay away from rye for the nonce, get a few cakes to go first. Or leave some of them cakes, and do a flat/bulk substrate with some of them- you know what you said upon joining this board, and to boot, how much more difficult that kind of thing is. Leave at least some of your cakes in kinder-garden.......

from what virtually everyone sez here, rye is one of the hardest to keep clean. Save it till you have a nice rotation going with extras....

go ahead, kill me. You're crazy. You'll get away with it.....

By onediadem (Onediadem) on Wednesday, December 05, 2001 - 11:39 am:

Ok Boomer. I just had such fabulous luck with the rye before. No contams at all, due to my extreme sterile teks. My contams came after, because I had totally bogus info about what to do after the rye had fully colonised. I know, that I can get jars of rye fully colonized without contams, and thought I would go that route, with the info I have learned about being able to case the rye without mixing it with other stuff. I will however, sit in yoga style, say ohmmm over and over again, until patience is my mater!! I will continue with my pf jars, until I have that down pat. I am just twitchin over here. Bad, Bad, Pam.
Love all ya,
The crazy lady in the woods.

By quote: (Quote) on Wednesday, December 05, 2001 - 01:03 pm:

correct, nuecrew.

By Eatyualive (Eatyualive) on Wednesday, December 05, 2001 - 09:28 pm:

hey snoopy,
i think that pic is pretty damn good. i am impressed. i would say no to use ground rye flour unless mixing it with something else. i tried to make pf jars once( in my stupidity) with rye flour and verm. it turned into dough and looked like i was trying to make bread. it is a waste of time. verm works ok but i would say to use coir or coco fiber it is very simple and yields better.

By Snoopy (Snoopy) on Wednesday, December 05, 2001 - 09:56 pm:

Hey eatyou thanx for the comment I just love your casings as I am sure almost everyone here does. I am thinking about trying some coir or coco in my next casing for that ability to keep moisture in like the verm, but to also give nuetrients(spelling) which the verm does not.

By ion ewe (Ion) on Wednesday, December 05, 2001 - 10:08 pm:

What nutrients? In coir? There's some fiber, maybe some left over fats from the coconut, some amino acids possibly, perhaps even some protein... but these are all at such miniscule levels. Unless I'm missing something, here... Which is always possible.


By Karna (Karna) on Thursday, December 06, 2001 - 10:59 pm:

I find that verm and peat/verm each have their adherents among cubie strains.
In the beginning I cased with wet verm only and swore by it, great yields
Then I couldn't find medium grade, so I switched to peat/verm. More easily adaptable, but have to be more careful about not using too much water. With verm you can flood it with water without too much worry (almost like a dunk). If you do this with peat, you're doomed.
Then medium grade made a come back and I started using it again being a fan of the least upkeep teks. However, at this time I was working with some different strains and found that unfortunately, while pf loved it, the others reacted with some antipathy. So back to peat/verm. Also medium grade verm took this window of opportunity and disappeared from the local market altogether.
So now peat/verm it is with some CaCO3 sprinkled directly on the crumbled cakes as well as liberally added to the peat/verm. Good results with different strains.
Watch for medium grade verm in an upcoming edition of "Where are They Now - Hard Rocks"