Originaly posted at Lycaeum
Date: Mon, 20 Dec 1993 00:31:52 UTC
I am an aspiring 'shroom grower myself. I have completed the single-strain
isolation phase and I am ready to move on to the grain cultivation stage. After
I have completed a harvest, I hope to post a list of my trials and tribulations
to 'alt.drugs' including any tips or hints I discover along the way. This article
contains one important tip. Read on!
P.D.A. and M.E.A. are great alternatives to buying pre-packaged agar from somewhere
like a scientific supply. I purchased 4 oz. of pre-mixed malt extract agar and
spent $20 for it...and when you use 15-20 g of that mix per liter, it's not
nearly as cost effective as doing it from scratch.
Please note that most of my info comes from McKenna's definitive book: _Psilocybin:
Magic Mushroom Grower's Guide_. No rights reserved, and while Terry's publisher
might have something to say, I think he would be happy to see the spread of
the information that leads to successful shroom cultivation.
I mixed up a batch of PDA (Potato Dextrose Agar) from scratch. I have had great
results and it's easy to make. After the recipe process, I'll explain how/where
to obtain the materials and what to look for. McKenna says:
For 1 liter total volume of liquid PDA agar you need:
250 g potatoes
15 g agar
10 g dextrose
1.5 g nutritional yeast (or yeast extract)
Shred the unpeeled potatoes into a colander and then rinse them for thirty
seconds with cold tap water. Combine the rinsed potatoes with one liter of water
and gently boilf for 30 minutes. Filter the resulting potato broth through muslin
or cheescloth and discard the potatoes. To the liter of potato broth add the
agar, dextrose and yeast which you have previously weighed out, mixed together,
and set aside. While stirring gently add in the mixed powdered indgredients.
Gently boil for ten minutes or until the solution is clear. Take care to not
allow the solution to boil over. Add enough water to return the total volume
of the solution to one liter. Pour the solution while still hot and liquid into
petri plates, baby food jars, or slant culture tubes. Use just enough to cover
the bottom of the containers, about 1/4 inch deep or a little more. The solution
may be allowed to cool or sterilized immediately.
There are a few different recipes for different types of agar. McKenna recommends
changing agar types every few batches to prevent your Psilocybe cubensis mycelium from
experiencing the "senescence" factor, or the tendency of the mycelium
to "age and lose vigor." Here are some other agar recipes, mixed and
used in much the same manner as PDA.
For 1 liter total volume of MEA you need:
20 g malt or malt extract (powdered or syrup)
25 g agar
0.1 g potassium dibasic (K2HPO)
0.1 g calcium carbonate (CaCO3) (basically powdered oyster shell)
Add these ingredients to one liter of boiling water. After they have dissolved
it is ready to be poured.
There is another agar recipe which McKenna says is good for long-term maintenance.
It is MYP or Malt-Yeast-Peptone agar. The procedure for preparing this mixture
is the same as for MEA.
For 1 liter total volume of MYP you need:
7 g malt extract (powdered or syrup)
1 g peptone or soytone
0.5 g yeast extract
15 g agar
A note on the ingredients. Agar (agar-agar) itself is a powdered extract of
the gelatinous elements of sea-kelp. It may be found in health food stores,
food co-ops or places that specialize in natural foods. It can be expensive
(I have seen it for $50 a pound) but you don't need much to make a batch.
Dextrose is CORN sugar and may be found for about $1 a pound at a beer/wine
brewing supply center. Be sure to get CORN sugar and not CANE sugar (sucrose).
The same goes for malt extract, easily found in syrup or powder form in a brewing
supply store, or in some health food stores.
Soytone and Peptone are commercial brands of a protein hydrosylate and can
be purchased form scientific or microbiological supply houses.
The other ingredients can be found at scientific supply houses and are definitely
not on any controlled subtance lists. This is one of the beauties of 'shroom
cultivation as opposed to manufacture of other substances.
Here's some info on agar sterilization. And by sterilization I am referring
to the use of a pressure cooker/canner which is a substitute for a lab- grade
autoclave. I don't know much about the kits you see advertised everywhere, but
these sterilization-free kits tend to suffer from a high contamination rate.
Even though I am relatively new to growing mushrooms, after nearly 50 cultures
cultivated in baby food jars in a few weeks, I have not had one contaminated
culture. You just need to sterilize properly and keep all you surfaces clean.
A fume hood is nice, but not necessary: I use a polyethylene tarp draped over
my table work-area. Be ruthless with the Lysol or whatever disinfectant you
use...but look out for the flammable ones (like Lysol) and keep them away from
And my tip on agar sterilization: don't overdo it! In McKenna's book, he cites
how the standard sterilization time at 250 degrees (15 psi) for agar is 15 minutes.
But he claims this is not long enough and recommends 45 minutes to an hour.
Presumptious of me as it is, I say NO! Several of my agar cultures were ruined
by the intense heat of the pressure cooker. After they were done, they would
cool but not congeal...the molecules that do the gelling had been severed by
the heat. They just sort of sloshed around in clumps and actually should set
into flat, glassine material (like JELL-O!). In a few experiments, I found that
250 degree, 15 psi was good, but I only needed to sterilize the cultures at
this temperature for 30 MINUTES. I have had no problems with contamination so
Moonflower's Cheap ---Rice Malt /alfalfa/ Brewer's Yeast Agar
1 ea Quart Jar (Mason/Ball type with lids)
Take 2 cups of rice and place in a 3 quart bowl or pan.
Pour approx. 1 1/2 quarts of clean (bottled or rev osmosis) water into bowl.
Stir in 1 cup of alfalfa (like in the health food stores) meal.
Add 1 standard dolomite (oyster shell-crushed) tablet and allow to dissolve
in resultant slop.
Allow to sit for 2 hours/stir every 20 minutes or so. It is ok to warm the
mixture to speed up the expression of nutrients, but cold soaking seems to be
the best. (takes longer, but has a better quality) The water should be about
70-80 degrees F. for best results not _chilled water.
Strain out rice/alfalfa and throw it away.
Mix 1 pkg of your regular baker's yeast into liquid and stir in.
Let the mixture sit for 30 minutes to an hour or until it is obvious that
the yeast are activated. (usually a foamy looking bubble mas will be floating
on top and the mixture may appear more opaque)
Strain out and throw away solid yeast grains. Boil the resultant liquid rapidly
for 5 minutes and then turn off the heat and add 18 grams of agar agar (aka
red algae) that you bought at the health food store.
Pour mixture into mason/Ball jar and put lids on (seal down).
Sterilize in pressure cooker for 20 minutes at 15lbs and allow to cool. (this
is at sea-level...people in high altitudes should consult a conversion table
for equiv. pressures and times)
You will now have 1 quart of a very good agar media for mycoculturing that
will support _luxuriant_ mycelial growth. It is more than sufficient for starting
spores as well and seems to produce a lot more "banding" than other
media I have tried. Banding is when the mycelia (dikaryotic) grows in a pattern
that resembles circles of threadlike fungal strands similar to tree rings on
the petri dish. I have seen carpophores form directly on the agar and fruit
in a covered dish on this media and permeation time seems to be cut in half
in grain media spawn.