Mushroom Growing by Mush Mush by Mush Mush © Mush Mush

Table of Contents:

Cultivation of Psilocybe cubensis on cased sterilised grain

Making grain spawn

What is grain spawn?

Containers

Glass jars

Microboxes

Filter patch bags

Closing the containers

Closing glass jars

Closing microboxes

Closing filter patch bags

Substrate recipes

Sterilisation

Inoculation possibilities

Spores in a watery suspension

Mycelium on agar

Mycelium on sterilised on grain spawn

Mycelium in a watery suspension

Inoculations in practice

Inoculation of jars and microboxes

Inoculation of bags

Incubation

Contamination

Refrigeration



Cultivation on cased sterilised grain

Overview of the procedure

Testing the colonised grain

Casing

Casing mixture recipe

Alternative mixtures and considerations

Heat treatment of the casing mixture

Pasteurisation in a microwave oven

(semi-)Sterilisation in a pressure cooker

Casing the colonised substrate

Casing jars

Cased trays

Fruiting the cased substrate

Cased trays that fail to fruit

Casing completely colonises but fails to form mushrooms

Mycelium doesn't colonise the casing surface at all

Strange growth is showing up on the casing surface



Cultivation of Psilocybe cubensis on sterilized rye grain

Preparation of rye grain spawn

Sterilization

Inoculation

Colonization

Casing of rye

Recipe and Preparation of the casing soil

Fruiting



Cultivation on riceflour cakes (short version)



Cultivation of Psilocybe cubensis on riceflour cakes

Introduction

Overview

Substrate containers

Preparation of the lid

Substrate preparation

Filling the jars

Sterilisation of cakes

Inoculation of cakes

Incubation of cakes

Fructification



Cultivation of Panaeolus cyanescens and Panaeolus tropicalis on sterilised substrate

Straw substrate preparation

Substrate Colonisation

Casing the substrate

Panaeolus fruiting

Cultivation notes



Cultivation of fruitbodies and sclerotia on sterilised grass seed

Preparation of the substrate

Sterilisation of seeds

Inoculation of seeds

Colonisation of seeds

Casing (for the cultivation of mushrooms)

Recipe and Preparation of the casing soil for seeds

Fruiting of seeds

Sclerotia



Making spawn for the woodloving outdoor species



Growing the woodlovers outdoors

Overview of procedure

Preparation of grain spawn

Growing mycelium on sterilised wood chips

Preparation of the wood chip substrate

Inoculating the wood chip substrate

Making the outdoor bed

Maintenance

Mushrooms!



Making a sporesyringe



Steam sterilisation

Typical sterilisation cycle

Sterilising sealed bags

Sterilising jars

Sterilising liquids

Sterilising other stuff



MushMush Notes

Preparing Agar

Pouring Petri dishes

Incubation of agar cultures

Storing cultures

Making a clean sporeprint

Substrates for Psilocybe cubensis

Substrates for Panaeolus cyanescens and Panaeolus tropicalis

Sterilization time

Casing soil

Sclerotia cultivation

Initiation strategy



Working with agar

What is agar?

Why is agar important?

Preparing nutrient medium

Pouring dishes

Preparing agar slants

Starting a culture from spores

Starting a culture from a fruitbody

Taping dishes and tubes

Storing slant cultures

Incubating cultures



Cultivation of Psilocybe cubensis on cased sterilised grain

Making grain spawn

What is grain spawn?

Grain spawn is rye, (or other cereal grain) fully colonised by mushroom mycelium. It serves two purposes:

1) As a carrier of mycelium into spawn larger amounts of substrate

2) As a substrate by itself.

Not all species will fruit directly from grain spawn. Psilocybe cubensis is one of the species that can do this, Panaeolus species generally will not fruit directly on (cased) grain. The latter species requires a dung-based to fruit on, although the mycelium will grow fine on rye.

The mycelium of most saprophytic mushroom species can be grown on rye.

Some rye grain.

Containers

Glass jars

Real canning jars are best because they can withstand numerous sterilisation cycles without problems. A cheaper alternative is to find the cheapest brand of applesauce or vegetables in a local supermarket and to discard the contents (not in the store!). When these jars are cleaned and have their labels removed they can be used. However, since these jars are not intended to be sterilised often they are much more fragile, especially after 2-3 sterilisation cycles. Metal lids, or lids made from polypropylene (PP) can be pressure cooked.

This symbol is depicted on most polypropylene items.

Microboxes

These polypropylene containers provide an excellent alternative to glass jars. They come with a filter fitted in the lid and the lid seals hermetically to the bottom. They can be pressure cook and be re-used over and over again. Because they are made from polypropylene there's no risk of injury from glass shards as there is with glass jars.

Filter patch bags

These bags are specially made for the production of grain spawn. Made of polypropylene they have a filter patch sealed to one side of the bag. Traditionally these bags are sterilised open and sealed afterwards but we have some tips on how to sterilise them sealed, look here. The bags need to be sealed with a good impulse sealer. Cheap household sealers will not work because the width of the seal is too small.

A 1000ml microbox and 720ml jar Filter patch bag and medium components

Closing the containers

Closing glass jars

For glass jars there are some options on how to close them. We prefer to use Tyvek or filter disks beneath the lids. Although it is possible to incubate the jars without some kind of filter, just with the lids loose, this is risky. Especially in somewhat drafty and/or dirty environments jars without a filter easily contaminate with airborne spores.

A hole should be drilled in the lids. In case of metal lids holes can be punched with a nail and hammer. The size and/or amount of the hole(s) depends on the type of filter that is used. If too much dehydration during incubation takes place more sheets of filter material should be used next time. Some experimentation may be necessary to find the optimum hole size and filter material.

Lid with a hole.

The jars are filled with rye and water then the filter material is screwed tight under the lid. The lid can be screwed tight during sterilisation since the filter will allow steam to escape.

Rye and water Rye and water combined in a jar Filter disk Tyvek filter

Lids on jars without a filter should never be screwed tight since the jars might explode/implode during sterilisation.

Jars are capped with a double layer of aluminum foil to keep the filter clean and dry for inoculation.

Jar with Tyvek filter Tyvek jar with the lid on Jar with filter disk Jar capped with aluminum foil

Closing microboxes

These polypropylene containers come with a tight fitting lid. The lid contains a filter but this filter does not allow rapid venting of steam. Therefore microboxes should never be sterilised with the lid closed. Closed lids will result in deformation or other damage to the jars.

The container is filled with rye and grain then the lid is put on loosely or closed for 3/4. One 1/4 of the lid should always remain open.

The boxes are capped with a double layer of aluminum foil. As soon as the boxes come out off the cooker their lids should immediately be closed.

One edge should be left open Microbox ready for sterilisation

Closing filter patch bags

With some care bags can be sealed before they are sterilised. For more instructions look here. Sterilising open bags is possible but bags should be sealed the moment they come out of cooker or they should be left to cool down in a running flow cabinet.

Water and rye are combined The bag is sealed with an impulse sealer A good double seal Bag ready for sterilisation

Substrate recipes

In general the more substrate is sterilised in a container the dryer it should be. Rye grain and water can be combined and subsequently sterilised. There's no need for pre-cooking the grain as is the case with birdseed. During the sterilisation cycle the rye grain will absorb the water but this will go a little uneven. The bottom kernels will be wetter than the top kernels so the jars need to be shaken while still hot to evenly distribute moisture throughout the substrate.

500 ml jar/microbox

125 g rye

160 ml water

1000 ml jar/microbox

250 g rye

280 ml water

filter patch bag (4 liters effective)

1600 g rye

1350 ml water

Sterilisation

Jars and microboxes up to 1000 ml are sterilised for one hour at 121° Celsius. Bags require much longer; up to three full hours. More details about steam sterilisation in general and how to sterilise sealed bags can be found here.

The first layer of bags The second layer of bags Flaps are folded down The rack on top is very important

As soon as the microboxes come out of the cooker the lids should be closed completely, simply by pressing them downwards. When they have cooled down completely they can be inoculated.

The correct sterilisation pressure Sterilised jar, rye has absorbed all water

Inoculation possibilities

Now that the substrate is sterilised and sitting comfortly in its container it's time inoculate. In theory one could keep the sterilised substrate indefinitely but in practice it's best to inoculate as soon as possible. As time goes by the substrate dries out and some contaminants may even be encountered after a few weeks of storage.

There are four practical means of inoculation:

1) Spores in a watery suspension (spore syringe)

2) Mycelium on agar (clone or multispore germination)

3) Mycelium on sterilised grain spawn

4) Mycelium in a watery suspension (liquid mycelium)

Spores in a watery suspension

A properly prepared or bought spore syringe can be used to inoculate sterilised rye. The hydrated spores easily germinate on the moist rye and form a mycelium. Often the first signs of germination can be observed after 3-10 days. Germination time depends on the strain and age of the spores. Well-hydrated spores germinate faster than those that have been just scraped off a spore print. When filter disks or Tyvek are readily available the syringe can be used to puncture the filter and to inject an amount of spore suspension. The amount of spore suspension used for one container depends on the availability of inoculant and the desired colonisation speed. More inoculant often results in somewhat faster growth. For jars and microboxes 1 ml of spore suspension would suffice. Of course, more spore suspension in combination with regular shaking of the jar would result in a (somewhat) faster development.

Bags are usually injected with 1-10 ml but they could very well be injected with up to 100 ml. Spore injection is an easy and efficient way for novice cultivators to inoculate small batches of spawn.

Mycelium on agar

Agar squares can be cut from a petri dish with a sterilised scalpel and these can be dropped into the jar. Since the jar has to be opened for this method to work an (improvised) inoculation hood is useful. One or more squares are dropped into the jar or microbox. These containers are are shaken and incubated.

This method will not work for bags since it's not practical to cut open a sealed bag to introduce the agar squares.

Mycelium on sterilised on grain spawn

In theory this would be the best and fastest way to propagate huge amounts of spawn but in practice it's not that easy. It's only possible to do these transfers in a totally sterile environment or huge amounts of contamination will be encountered. We found that this method has limited potential for home cultivators.

Mycelium in a watery suspension

This is the way to go if you have serious money to spend and have very good sterile techniques. It's possible to create huge amounts of liquid spawn from a single Petri dish by chopping it up in a laboratory blender and then diluting this broth The total amount of mycelium is of less importance than the amount of water it is delivered with. Although initial startup growth is slow, it will start in many points throughout the substrate.

Inoculations in practice

In general the following goes: the longer the sterilised substrate is exposed to the outside air during inoculation, the cleaner the environment should be. When inoculating just a few jars by puncturing the lid with a syringe needle, a cleaned tabletop in the kitchen should be fine. When inoculating open bags with grain spawn a professional flow cabinet is indispensable. Airborne contaminants often settle on the top of the substrate, so when nasty fungi start to grow on top of the inoculated substrate the substrate was probably exposed to unclean air for too long.

In theory one could get a 100% success rate in a flow cabinet but in practice even under the most hygienic conditions contaminations will be encountered. Contamination rates below 10% can usually be considered good.

Inoculation of jars and microboxes

The easiest method to inoculate jars and microboxes is with a syringe with spore-/mycelium-suspension. The needle of the syringe is heated until red hot and left to cool for 10-15 seconds. The aluminum foil of a jar is removed and excess moisture is wiped off with a clean tissue. The filter (Tyvek/filter disk) is punctured with the needle and some (1 ml) of suspension is injected into the substrate. The needle is withdrawn and the hole is immediately sealed with a drop of hot glue. Jars can then be shaken and incubated. Instead of glue, a piece of tape could also be used but we found that hot glue is the perfect way to seal jars. Even a small and cheap glue pistol will do the trick.

Puncturing the filter ... and glueing it shut

When the lid or filter can not be punctured as is the case with microboxes, the lid should be opened just a crack and the needle can be introduced through there. The needle is withdrawn, the lid is closed and the microbox/jar is shaken and incubated. Since there is more air exposure with this method an (improvised) inoculation hood is desirable.

A jar inoculated with a spore syringe A microbox inoculated with a spore syringe

When inoculating with agar squares there's no choice but to open the lid just enough to introduce the agar. Again, an (improvised) hood is desirable for this kind of work.

Squares are cut from the agar These squares are dropped on the substrate

Inoculation of bags

When working with sealed bags the inoculant can only be introduced through means of injection. It's not practical or advisable to cut open a sterilised bag only to re-seal it after inoculation. Working with open bags is not advisable for those without a laboratory and a flow cabinet. Grain to grain transfers will not be discussed here.

The injection site on the bag is cleaned with an alcohol soaked tissue, then the (flamed) needle of the syringe is introduced. Some liquid is injected into the bag (1-200 ml) and the needle is withdrawn and the hole is sealed with a drop of hot glue. A spore syringe is fine for this.

the bag is punctured with the needle The hole is glued shut

Below you will find a summary of the inoculation method MushMush employs. It involves chopping up an agar culture and using a peristaltic pump to deliver the diluted mycelium to the sealed bags. We understand that there are few people that might actually try this (the equipment is pretty expensive) but it might give you an idea of the possibilities.

Colonised agar is transfered to a sterilised blender Sterile water is added and the agar is chopped up The blended agar is divided over two bottles with sterile water A peristaltic pump is used to dispens the mycelium suspension The pump is controlled with a foot pedal switch A short thick needle is used to inject the liquid mycelium The bag is punctured and the pedal is pressed A cheaper solution is to use a self-filling syringe

Incubation

The inoculated grain should be incubated at the temperature that is optimal for the species being cultivated. A temperature that is too low will result in slow germination/growth. A temperature that is too high will make the mycelium exude yellowish metabolites (sweat) that eventually sicken the spawn.

Since the growing mycelium produces heat a rise in temperature should be anticipated. A few jars will probably not heat up to critical temperatures but developing spawn bags might very well, especially in the summertime. Bags that stand at too high a temperature will often contaminate will thermophilic moulds (often black pin moulds). Take extreme care when handling contaminated substrate as some species of moulds and bacteria can cause serious diseases in humans.

To prevent condensation in the containers they should be kept at a temperature that is as constant as possible.

To speed up development jars and bags should be shaken regularly to distribute the colonised kernels throughout the substrate every few days. When the grain is completely covered with mycelium it's ready for further use.

Microbox during colonisation Microbox totally colonised Bag during colonisation Bag totally colonised

Contamination

Contaminated spawn will be encountered for sure. Contaminants show up in the form of fungi and bacteria. Fungi often grow whispy or powdery and come in an assortment of funky colours: blue, green, pink etc. Bacteria show as a slimy film on the grain kernels. When in doubt, take a smell at the the filter of the suspected container. A medicinal or musty odor often indicates fungi while a sour/sweet/rotten or alcoholic smell is a sure giveaway for bacterial contamination.

Perhaps needless to say, the contaminated spawn should be discarded. Bags can be thrown out as a whole. Jars should be cleaned out but only after they have been sterilised to kill the contaminants. Some contaminants can cause serious diseases in humans and the fact that you are reading this probably means that you are not experienced enough to distinguish harmless from dangerous contaminations. Never underestimate the health dangers associated with contaminants!

A bag contaminated with mould A slimy bacterial contamination

Refrigeration

The spawn of most species can be refrigerated until ready for use. Although vitality declines most species can be stored for a few weeks at 4-7°C. Panaeolus mycelium however should never be refrigerated because it will loose it's vitality within a few days.

Cultivation on cased sterilised grain

Overview of the procedure

Mycelium of Psilocybe cubensis is grown on sterilised grain. The colonised grain is covered with a wet soil like mixture, this is called 'casing'. The mycelium will grow through the casing layer and will partly colonised the casing surface. Now the casings are exposed to fruiting conditions and the casing is kept moist. Mushrooms will form on the casing layer.

A bag of healthy spawn.

Testing the colonised grain

Before casing the colonised grain should be tested for contamination. This is done by shaking the spawn containers (bags or jars) 24 hours before putting on the casing layer. If the grain is contaminated with molds the whole bag or jar will turn green, blue or grey. Bacterially contaminated grain will not recover at all and will often smell very foul (sour, alcoholic or rancid).

If the spawn recovers nicely it's ready for use.

Casing

Once the grain is completely colonised it needs to be 'cased' before mushroom formation will take place. 'Casing' is the process of putting a wet soil like mixture on top of the colonised substrate. This is done for 4 important reasons.

1. Preventing the substrate from drying out

Mycelium is sensitive to dry air. Mycelium that is exposed to dry conditions for too long may form a leathery matted surface on which no mushrooms will grow. The moist casing layer prevents this and the mycelia will form a healthy network in the casing layer. The casing surface should be kept moist by regular waterings.

2. Storing and supplying water to the growing mushrooms

Developing mushrooms pull a lot of moisture from the casing layer. Since moisture in the casing soil can be replenished by watering it functions as a water reservoir for the growing mushrooms. A casing layer should be able to absorb water and to supply it to the mushrooms.

3. Providing a good microclimate for pinhead formation

With all small bumps and valleys the rough surface of a casing layer provides a good humid and protected environment for young mushrooms to form.

4. Supporting the growth of beneficial microorganisms

Although Psilocybe cubensis can fruit on a sterilized casing layer many species require certain bacteria to be present in the casing soil. This has consequences for the type of heat treatment that is chosen. A brief pasteurization will hinder most animal and fungal competitors in their growth while leaving most bacteria unhindered. Complete sterilization in a pressure cooker may only be used for species that do not require these soil bacteria.

Casing mixture recipe

The following recipes have proven themselves over the years as good all round casing mixtures:

10 parts of peat

5 parts of coarse vermiculite

2 parts of limestone

and

10 parts of wetted coco coir,

5 parts of coarse vermiculite,

1 part of limestone

(all ingredients by volume)

The exact ratio is not that important. As long as sufficient limestone is added the pH will rise to between 7-8. Many types of limestone are available differing in origin, composition and grit size. We prefer Marl (coral derived limestone) but most other types will do just fine. The coarser the particles the more is needed to to obtain a proper pH. Since peat is very acidic in nature it's wise to always add more limestone than to coco coir. It's nearly impossible to overdose on limestone.

The three ingredients for casing mixture

The ingredients are mixed in a bucket or bag in dry form and large particles such as undecomposed wood are removed. These particles might give contamination problems later on.

Once the ingredients are well mixed water is added. The object here is to get as much water into the mixture as possible without turning it into mud. It's wise to hold some dry ingredients apart in case the mixture gets too wet by accident. By adding some dry ingredients the excess water can be absorbed.

Proper wetness is achieved when a handful of mixture does not leak water when held loosely. The mixture however should release plenty of water when squeezed. It should feel wet, not soggy.

Casing mixture dry form Casing mixture wet form

Alternative mixtures and considerations

The above recipes are not holy. We have achieved good results on many different types of casing mixtures. Some cultivators use plain vermiculite with great results but this is not advised for novice cultivators. Moisture content in plain vermiculite is very difficult to observe by eye (very wet and nearly dry vermiculite look the same). Vermiculite can be omitted in the above recipes but the mixture will be less rough in structure.

An important thing to mention is that the casing layer is not intended to supply the mycelium with nutrients. Any easily digestible compounds (whether sterilised or not) in the wet casing layer will surely contaminate. The conditions for the growth of competiting organisms are near optimal in the wet and warm casing layer. Additions such as flours, malt extract or sugars will not boost yields but only lead to contamination.

Heat treatment of the casing mixture

To free the casing mixture of any unwanted organisms (mainly fungal and animal competitors) it can be heat-treated. Although some cultivators get away without any heat treatment we feel that this is bad advice.

Untreated mixtures (except plain vermiculite) are much more likely to contaminate than pasteurised or sterilised mixtures.

There are two good methods for home cultivators:

Pasteurisation in a microwave oven

This method will not completely sterilise the mixture but will suffice for most cultivators. Most contamination problems associated with the casing layer involve fungi. Most of these fungi are killed are relatively low temperatures which are easily reached by microwaving.

The mixture is put in polypropylene bags or jars and some extra water is added to make up for evaporation. Care is taken to leave the lids a crack open or to open the bags to let the steam escape. Not doing this may result in an explosion!

The microwave is turned on at full power for approximately 30 minutes (for one 5 liter bag of soil). The bag is take out of the microwave with heat-insulating gloves, sealed with an impulse sealer or simply taped shut. When the soil has cooled down it's ready to use. Soil prepared in this manner is often a little on the dry side. Clean water may be added after sterilisation but before applying the mixture.

(semi-)Sterilisation in a pressure cooker

This method will, depending on the duration of the treatment, pasteurise, semi-sterilise or completely sterilise the casing mixture.

When a big pressure cooker is available this method may be faster then using a single microwave oven. The mixture is put in bags or jars and these are put in a pressure cooker. The contents is sterilised for the appropriate amount of time and left to cool in a clean place. Here again great care is taken to leave jars always a crack open to prevent them from exploding/imploding. When the mixture has cooled down it's ready to use.

As a rule of thumb for the appropriate sterilisation duration we take half the time it would take to completely sterilise the same amount of rye grain. For a filled 20 liter cooker this means 1 hour at 121°C. This treatment does not completely sterilise the mixture but will give a very good resistant casing layer. For complete sterilisation use the duration for the same amount of grain.

Casing the colonised substrate

Casing jars

If the colonised substrate is in (wide-mouth) jars it can be left in the jars, however the volume/surface ratio is not optimal. Still substantial yields can be achieved with this method. The big advantage is that the complete casing process is very simple and leaves very little space for contamination.

Jars are cased with 1-2 cm of wet casing soil which is leveled by tapping the jar. The cap is replaced and the jar is incubated in the dark until the mycelium is poking up through the casing layer. Cased jars should be kept at the same temperature as the incubating spawn (25°C). At this stage the cap is removed and the jar is wrapped in aluminum foil. The foil is to prevent exposure to light of the colonised substrate. Not doing so will result in mushroom forming inside of the jar instead of on the casing soil.

A fruiting cased jar

Cased trays

When the colonised substrate is poured into trays which are cased a much better volume/surface ratio can be achieved. This results in more mushrooms in less time compared to cased jars.

First the grain is broken up by shaking. The broken up grain is divided into 1 liter trays and subsequently cased with 1-2 cm of casing mixture. The casing can be applied with a clean large spoon or with your hands wearing latex gloves.

Spawn before ... ... and after shaking The spawn is poured into the trays ... ... and is topped off with casing mixture

The cased trays are covered with aluminum foil and incubated in the dark until the mycelium is poking through. Cased trays should be kept at the same temperature as the incubating spawn (25°C). Now the foil is removed and the trays are exposed to fruiting conditions. Normally this is one week after casing.

The cased trays are covered with aluminum foil After a few days mycelium will be growing through the casing layer

Fruiting the cased substrate

Some cultivators use very elaborate set-ups with humidifiers, cool-mist devices and such. Psilocybe cubensis is an easy mushroom to fruit and we have never found these necessary.

A very space efficient fruiting container consists of a simple transparent plastic bins covered with polyethylene sheeting. There are stackable types available which allow one to grow in 10 bins or more on top of each other. Needless to say it can't get more space efficient than this. For air exchange some holes are drilled in the sides of the bins. These holes can be covered with mesh to keep out flies.

The fruiting container consists of a simple plastic bin The bin is covered with plastic sheeting to maintain the proper humidity After 10 days small mushrooms form The casing soil is kept moist all the time

In our case five trays can be put in one bin and the evaporation of the casing surface is enough to maintain proper humidity inside the bin. The holes provide some air exchange. We always cold-shock the harder-to-fruit strains (we put them in the fridge for one night before putting them in the bins). For easy fruiting strains (i.e. Equador cubensis) this is not necessary.

As for as temperature is concerned: Psilocybe cubensis is an easy mushroom. From our experience trays and jars will fruit in the range between 19-30°C, Although a temperature of 25°C is most desirable. In other words: if the temperature is comfortable for you, it is too for the mushrooms!

The casings need some light. In the dark mushrooms will not form! Any kind of light will do (daylight, fluorescent, incandescent) but they should not be exposed to full sunlight for obvious reasons. If the casings receive (too) little light mushrooms will develop long and spindly.

The casings are misted each day and the casing is never allowed to dry out. Directly after a flush is picked watering is increased because the maturing mushrooms pull a lot of moisture from the casing soil. It's very difficult to give explicit directions on a watering regime. One has to develop a 'feeling' for it.

Depending on the strain the first pinheads will appear 6-15 days after putting the casings in the bins. The mushrooms will mature in 5-7 days after which they can be picked. We normally let the casings produce 3 flushes, but they may (when watered properly) produce as much as six flushes! The surface of the casing is kept clean by removing aborted mushrooms. If contaminations show up on the casing surface it's often better to throw the trays away.

A fruiting cased tray A bin with 5 fruiting trays

Cased trays that fail to fruit

Casing completely colonises but fails to form mushrooms

When the environmental conditions aren't right for the strain being cultivated the mycelium will not form mushrooms but will continue to colonise the casing surface. If the situation is not corrected the trays soon become useless. The matted mycelial surface dies back and forms a crust that prevent the casing from absorbing moisture which results in drying out and eventually death.

In general this is caused by:

a) A lack of fresh air

b) A relative humidity that is too high

c) A temperature that is too high

d) A combination of the above.

Although some strains have more of a tendency to colonise the surface a fully colonised casing (no casing soil visible) is undesirable. To correct this situation the surface should scratched open with a clean fork to a depth of approximately 1 cm and environmental conditions should be adjusted to allow fruiting.

Mycelium doesn't colonise the casing surface at all

If the casing doesn't show any mycelium poking through within a few days the casing soil is probably too dry. Mycelium will grow wispy and thin in dry casing mixture. There is no objection to watering the trays before they are exposed to fruiting conditions but it's wise to wait at least one day after casing to allow the mycelium to recover.

Strange growth is showing up on the casing surface

Various molds may show up in the casing soil. Although mushrooms may still be formed on the contaminated casing it's wise to throw them out as they pose a risk to other trays nearby. A properly heat treated mixture that contains no nutrition will give very little problems with mold.

Green and blue molds can often be traced back to contaminated grain spawn. It's important to make sure that the spawn that is cased is absolutely clean. A simple test is to shake to spawn 24 hours before casing. If the mycelium recovers it's fine to use. If it does not or strange colors or structures (powder-like growth) appear the spawn is contaminated and should be thrown out.

Cultivation of Psilocybe cubensis on sterilized rye grain

We cultivate Psilocybe cubensis on sterilized rye grain. This species can be grown on a wide variety of substrates such as rice, birdseed, pasteurized straw, compost and dung. We however think that, of all of these, rye grain is the most suitable for the small-scale cultivation of Psilocybe cubensis for research purpose because it's both cheap and easy to work with. Most other grain types have the disadvantage of having to be boiled or steeped before sterilization or else the kernels will clump together. Cultivating mushrooms on straw, compost or dung is possible but an art in itself.

Preparation of rye grain spawn

We prepare rye grain spawn by combining equal volumes (1 cup) of rye grain and water in a jar. In our case this comes down to (roughly):

175 grams of rye

230 ml of water

We use 720 ml jars with metal lids. After the water and rye have been filled into the jars, the lids are put on but NOT screwed tight! The lids MUST remain loose! Then a double layer of tinfoil is crumpled over the lid and top part of the jar. Now the jars are ready for sterilization. As an extra precaution some kind of filter (filter disc, Tyvek) can be inserted under the lid. For this method the lids must be punctured to facilitate air exchange.

Different ratios of rye and water have been suggested by literature. We recommend you do a test batch with different ratios of water and rye to see what works best for you. The 1:1 ration we use contains the maximum amount of water the we could use. When using larger volumes (big jars or bags) less water should be added or the bottom kernels will turn to brown goo. When using the colonized rye grain to directly fruit the grain can be somewhat wetter then when it's used to inoculate (non sterile) bulk substrate. Exploded kernels with their starchy inside exposed can flourish with bacterial bloom upon contact with non sterile materials.

Sterilization

The jars should be sterilized in a pressure cooker or autoclave, a normal pot will NOT suffice. First a layer of water is poured into the cooker. The jars are placed in the pressure cooker making sure that the lids are loose!

Now sterilize the jars for one hour according to the directions supplied with your pressure cooker. If you are using bigger jars then the sterilization time should be prolonged. (we sterilize 1.5 litre jars and spawnbags always for 2 full hours). Once the cooker is no longer under pressure the jars should be taken out and the grain in the jars should be shaken loose to mix the wet and dry kernels. The jars should then be allowed to cool in a clean place. Always check the jars for cracks before shaking! When the jars have cooled to room temperature inoculations can take place. As the jars are cooling down the lids should remain loose or else they will form a vacuum inside of the jar. When this vacuum is broken, dirty air is sucked inside and the jar will most likely contaminate.

Inoculation

When the jars have cooled down completely they are ready to be inoculated. If you inoculate the jars while they are still hot the spores or mycelium might get killed. You can use a spore syringe, mycelium syringe, agar squares or whatever kind of inoculant you want. The most important thing to remember is to WORK CLEAN!

When using syringes always flame the needle before commencing inoculations. When using agar squares always flame the scalpel! Be careful!

ALCOHOL, LYSOL AND MOST OTHER DESINFECATNTS ARE HIGHLY FLAMMABLE!!!

Even a simple hood made of a cardboard box prevents prevent drafts and subsequently contamination. Do not expose the sterilized grain to air longer then absolutely necessary. Open the lids of the jars just a crack and work swiftly. After inoculation the lids of the jars are closed and the jars are shaken. Then the lid is loosened again so the mycelium will be able to breathe.

Use your common sense and do not put yourself in risky situations. Again, most disinfectants are both toxic and flammable. When working in the presence of an open flame do not use any kind of other flammable materials. Also, do not overdose on disinfectants, most are seriously dangerous to your own health.

UV disinfectant lights are dangerous as they can cause damage to your eyes and cause skin cancer.

Colonization

After inoculation the jars are put in a clean and draft free location. Mycelial growth has its optimum at 30°C, but beware! Incubating jars generate heat themselves! The mycelium will grow in a wide range of temperatures. We normally put our jars at room temperature (20°C) or slightly higher. When mycelium starts to grow in only a few spots we shake the jars to redistribute the colonized kernels. This speeds up colonization dramatically. Depending on the temperature and the method of inoculation the grain can be completely colonized in 5-20 days.

Casing of rye

When the grain in the jars is completely colonized it needs to be cased. For this purpose we use 1-litre disposable plastic trays. The colonized grain kernels of one jar are shaken loose are poured into a tray. If there are lumps within the grain these can be broken up with the clean rim of the jar. The surface of the grain is leveled evenly. Using a big spoon and a fork the grain is now covered with a thin layer (1.5-2.0 cm) of casing soil. We always try to keep the casing surface even while at the same time keeping it rough (with small valleys and hills) The cased tray is then covered with tin foil and put in a clean location (20-25°C). Within a few days you will notice the mycelium growing through the casing soil. Depending on the strain (some strains fruit earlier and easier then others) the casings are now ready to be exposed to air and light to start the fruiting cycle.

Recipe and Preparation of the casing soil

We use the following recipe:

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.

Fruiting

Some cultivators use very elaborate set-ups with humidifiers, cool-mist devices and such. We have never found this necessary. The fruiting containers that we use consist of simple clear plastic bins that are covered with polyethylene sheeting. These bins are stackable and thus very space efficient. For air exchange some hole are melted in the sides of the bins. These holes can be covered with mesh to keep out flies.

Basically, five cased trays are put in one bin and the evaporation from the casing surface is enough to maintain the proper moisture inside the bin. The holes provide some air exchange. We always cold-shock the harder-to-fruit strains (we put them in the fridge for one night before putting them in the bins). For easy fruiting strains (i.e. Ecuador cubensis) this is not necessary.

The casings are misted each day and the casing is never allowed to dry out. Directly after a flush is picked watering is increased because the maturing mushrooms pull a lot of moisture from the casing soil. It's very difficult to give explicit directions on a watering regime. You will have to develop a 'feeling' for it.

Depending on the strain the first pinheads will appear 6-15 days after putting the casings in the bins. The mushrooms will mature in 5-7 days after which they can be picked. We normally let the casings produce 3 flushes, but they may (when watered properly) produce as much as six flushes! Keep the surface of the casing as clean as possible by removing dead pinheads (aborts) as these can lead to molds showing up on the casing surface.

Cultivation on riceflour cakes (short version)

This document gives instructions on the cultivation of Psilocybe cubensis on a sterilised substrate of riceflour, vermiculite and water.

These polypropylene jars are used. They can withstand the heat of a pressure cooker. Of course glass jars can be used just as well. Four holes are poked into the lid with a sharp pointy object (a syringe needle for instance). If you are using glass jars with metal lids you can use a nail and a hammer to punch four holes into the lid.

The two main ingredients: vermiculite and brown riceflour.

First the dry ingredients are mixed: 4 cups of vermiculite, 1.5 cups of riceflour.

Two cups of water are added and everything is thoroughly mixed. The resulting mixture will look like this.

The jars are loosely filled with this mixture. The part of the jar above the substrate is cleaned with a paper towel. A layer of dry vermiculite is put on top of the mixture. This acts as an extra barrier for contaminants.

The lids are put on. And a double layer of tinfoil is crumpled over the jars.

The jars are put in the pressure cooker... and sterilised for 1 hour.

The jars have cooled down. The needle of the syringe is flamed...

...and the tinfoil is removed. The jar is inoculated through the four holes that were made in the lid. 1 cc should be enough for one jar. More sporewater can result in faster colonisation.

The tinfoil is replaced and the jars are put in a clean warm environment. The jars will colonise completely in 15-30 days (depending on strain, substrate, temperature and volume of sporewater used.

When the substrate is completely colonised the cake is taken out of the jar and put in the terrarium. We found that a plastic tray with wetted vermiculite inside an filter patch bag works perfectly for single cakes. Depending on temperature and strain mushrooms will appear in 5-20 days.



Harvest time!

Cultivation of Psilocybe cubensis on riceflour cakes

Introduction

The methods described here are generally known as the "PF-tek", although we made some useful adaptions here and there. The cultivation of Psilocybe cubensis on riceflour cakes is generally considered easier than cultivation on cased rye grain and is a method often employed by novice cultivators. A properly prepared and inoculated cake may produce up to 200 grams of fresh mushrooms (500 ml cake) in three flushes.

All cubensis strains can be grown on these cakes, even those that are somewhat harder to fruit on cased rye grain.

Overview

Mycelium of Psilocybe cubensis is grown on a sterilised substrate of brown riceflour, vermiculite and water. Substrate jars are prepared and subsequently sterilised in a pressure cooker. Inoculation is done by injecting spores with a syringe. After colonisation the substrate cakes are taken out of their containers and placed on wet vermiculite in a filter patch bag. After some time mushrooms form on the riceflour cakes. After the mushrooms have been picked the vermiculite is re-moistened to allow for a second and third flush.

Substrate containers

Glass jars can be used. Canning jars are the best but it may be difficult to locate them. An alternative that can be found in the supermarket is 'Bon Maman' jelly which comes in typical looking jars with a red/white blocked lid. These jars are good although a little on the small side.

Jars need to be non-tapered (no shoulders) or the colonised cake can not come out without smashing the jar.

These jars should be cleaned out... and have their labels taken off

A very suitable container is the microbox: A non-tapered polypropylene jar with a filter in the lid. These jars can be pressure cooked, are reusable and provide an excellent alternative to glass jars.

Preparation of the lid

The lids will need to be fitted with 4 inoculation holes. A heated needle or pin can be used to melt holes in the lid of the microbox.

With a hammer and a small screwdriver (or similar object) holes can be punched in metal lids of glass jars.

The holes are spaced evenly apart near the edge of the lid.

With a screwdriver and a hammer holes are poked A metal lid showing the correct location of the holes

To prevent the entry of contaminant organisms into the jars, these holes are taped shut, only to be opened for a few seconds during inoculation. Pieces of tape are prepared by folding back one end onto itself. This makes it easier to remove them during inoculation. The pieces of tape are then placed over the holes.

This metal lid is ready As is this microbox

Some types of tape can not be used. These will melt or lose their stickiness. Still we found that most types can be pressure cooked with reasonable success although they might curl up a little on the edges.

Polypropylene or nylon tape generally works fine. Masking tape can be pressure cooked but some types might harden out during sterilisation.

If suitable tape can not be found it's possible to sterilise the jars without tape and to tape the holes directly after inoculation. This however, is not recommended because of increased contamination risk.

Substrate preparation

The mycelium will be cultured on a substrate composed of brown riceflour, vermiculite and water.

Vermiculite and brown riceflour

Substrate recipe:

1,5 parts brown riceflour

4 parts vermiculite

2 parts water

(all by volume)

The mycelium will have difficulty growing in a substrate that does not have the correct moisture content.

First the dry ingredients are mixed. Then, while stirring, the water is slowly added.

The dry ingredients are mixed Adding the water

The finished substrate should not be soggy. If too much water was added and the substrate ends up too wet, some dry vermiculite/riceflour can be added to absorb excess moisture.

A properly prepared batch of substrate

Filling the jars

The jars are filled with the freshly prepared substrate. It's best to avoid having to store the substrate for longer than a few hour since bacteria will flourish in this moist, nutrient-rich medium.

The substrate is spooned loosely into the jars and compacted lightly by tapping the jars. Approximately 2 cm is left between the top of the substrate and the lid of the jar. This space is filled with a layer of dry, clean vermiculite. Since clean vermiculite does not support the growth of any competiting organisms, this layer helps to prevent the entry of contaminant organisms into the substrate during inoculation and incubation.

The rim is cleaned Clean vermiculite is put on

In the case of a microbox the lid is closed for 3/4 or left loosely on top of the jar.

Microboxes should never be fully closed during sterilisation or they will implode/explode and/or deform!

A filled microbox, lid 1/4 open Filled glass jars

Screw-type lids of glass jars are put on loosely but never screwed tight.

Both types of container should be covered with a double layer of aluminum foil to keep the lids in place and to prevent them (and the tapes) from getting (too) wet.

The lid should still be loose Ready for sterilisation

Sterilisation of cakes

Originally the PF-tek uses a sort of semi-sterilisation in a normal pot at 100° Celsius. The results of this method are unpredictable to say at the least. Therefore it will not be discussed here.

The only proper way to sterilise the riceflour substrate is with a pressure cooker. For more information about pressure cooking look here.

Both types of jars are sterilised for 60 minutes at 121° Celsius. Every jar is inspected before it is put in the cooker to make sure that the lid is still on loosely, or in the case of microboxes, the lid is at least 1/4 open.

Again, the lids should be loose!

When letting the jars cool down, make sure that the lids are still on loosely. For microboxes the lids should preferably be closed completely as soon as they come out of the cooker. The jars/microboxes are left to cool in a clean spot.

These jars are hot! The lid of the microbox is closed

Inoculation of cakes

Once the jars have cooled down completely to room temperature they can be inoculated with spores. A spore syringe (bought or self-made) is used to inject the spores into the substrate so that they can germinate and form a mycelium.

Although the risk of introducing contaminants into the substrate is pretty small because of the small inoculation holes, inoculation should preferably take place in a clean environment. A flow cabinet is best but a glovebox or improvised inoculation hood will also reduce the amount of contamination. The table top is cleaned with alcohol or lysol and remember as always: BE CAREFUL WITH ALCOHOL AND LYSOL IN THE PRESENCE OF A OPEN FLAME!

Just for inoculation the screw-type lids should be screwed tight to prevent accidentally tipping them off. After inoculation, during incubation these lids should be loosened again. The foil is taken off and replaced after inoculation. For the microboxes the foil can be discarded after inoculation.

Any moisture that may be present on the lid is wiped off with a clean tissue.

The needle of the spore syringe is flamed until red hot then left to cool for 10-15 seconds. The needle may not touch anything or it should be flamed again.

The needle is heated

The tape of one of the inoculation holes is peeled back and the needle is inserted through the inoculation hole, through the dry layer of vermiculite on top, aimed at the glass. 1/4 ml (or more) Is injected in the substrate. Then the needle is pulled back, the tape is replaced and the next hole is inoculated in the same way. It's not necessary to sterilise the needle after every hole but it's advisable to do this in between jars to prevent cross contamination.

The aluminum foil is replaced on the glass jars and the lid is loosened again. For microboxes the aluminum foil can be discarded.

Aimed at the glass microbox inoculation

Incubation of cakes

Tha cakes should be incubated in a warm, clean and dark location. Since the microboxes have an air filter they can be placed virtually anywhere. They will not suffer from air contamination even in the most dusty environments. The glass jars however do not have filter and care should be taken not to expose them to drafts.

The temperature should be between 20-30°C and the jars should be kept in the dark. Early exposure to light may lead to the formation of mushrooms while the substrate is still partly uncolonised. For this reason the jars should be disturbed as little as possible. A minute of light each day will not make them pin prematurely but an hour may.

Incubation

A few days after inoculation, spots of white fluffy mycelium should be visible. These are the germinating spores. In the following days the mycelium will colonise the riceflour substrate. Often the mycelium will change from fluffy to threaded. These threads are called 'rhizomorphs' and are considered a good thing. Good fruiting cakes often showed strong rhizomorphs during colonisation.

Colonising glass jar Colonising microbox

Depending on many factors (temperature, substrate composition, mushroom strain etc.) the cakes will be colonised in 7-20 days.

A week later A week later

Once the substrate is totally colonised by the white mushroom mycelium the jars can move to the next step. The dry layer of vermiculite on top usually does not colonise but that's ok.

Growth of any other shape or color than the white mushroom mycelium, except maybe from a little blueish tone, can be considered a contamination. Contaminated cakes should be discarded. Although many contaminants are harmles some are toxic and some can cause disease in humans. Therefore contaminated jars should be thrown out completely or they should be sterilised in a pressure cooker before being emptied out. Contaminated jars should NEVER be emptied before having been sterilised.

Fructification

Vermiculite (preferably fine) is soaked and drained to achieve a maximum water content without leaking. A layer of 2 cm is put in a disposable tray. A colonised cake is tapped loose from the jar and placed on the wet vermiculite. The tray with the colonised cake is put in a filter patch bag which is closed on top with two paperclips.

This one is ready The cake is loosened It is "birthed" The cake in its "terrarium"

The bag is put in a place where it receives some light (no full sun!) and where temperatures are between 20-30°C. No care is necessary from this point on until the first flush of mushrooms is picked.

The cakes will become fluffy in the next few days and the mycelium will start to grow into the wet vermiculite. The wet vermiculite supplies water to the cakes and this allows for more mushrooms without the need for dunking/soaking.

Rhizomorphs on the bottom of a cake

For most strains pinheads will appear after approximately a week. These are usually located on the bottom (former top) of the cake where most moisture is available. They first appear as small (<1 mm) white dots, that over the course of 1-2 days will slowly take on a mushroom shape. They will grow out to mature mushrooms in 5-7 days.

The first sign of mushrooms The dots take on a mushroom shape Young mushrooms One happy cake!

Mushrooms are picked before or just after the veil has teared. Mushrooms left to mature will sporulate and color the mushrooms black. If one desires to make sporeprints of course the mushrooms should be left to mature.

Cambodia cubensis Cambodia cubensis The veil has just teared Sporulation

Once the first flush is picked, the vermiculite in the tray is watered heavily with a spray bottle to replenish the lost moisture. This will allow for a second flush or, when repeated, even a third flush.

Watering will allow for second flush

Cultivation of Panaeolus cyanescens and Panaeolus tropicalis on sterilised substrate

Straw substrate preparation

Substrate for the cultivation of Panaeolus cyanescens and Panaeolus tropicalis can be prepared in the following manner:

Ingredients: Dried cow dung, vermiculite and soaked straw (submerged in water for 12 hours)

For 4 standard spawn bags we use: 1/2 kilogram dry straw, 4 liters of dried dung, 3 liters of vermiculite and 3-4 liters of water.

The dung and vermiculite in dry form are mixed. Water is added and the mixture is stirred (Make sure that the mixture is not too wet as loose water will often result in bacterial contamination later)

This mixture will look something like this. The straw is added...

and mixed in thoroughly Close up (looks nice doesn't it ;-)

The substrate is divided over four autoclavable spawnbags (with a filter patch) The flaps are folded and the bags are put into the pressure cooker. A lid is put on top to prevent the bags from blocking the steam valve

After sterilisation (2 full hours!) the bags are allowed to cool down in the flowcabinet. Two jars with Panaeolus cyanescens spawn on rye to be used for the inoculation of the substrate. Note that Panaeolus species do not colonise grain as densely as for instance Psilocybe cubensis.

The bags are opened in the flowcabinet (only touch the outside of the bags!) and each bag is spawned with 300 ml of spawn by means of free pouring. The bags are sealed with an impulse sealer.

Substrate Colonisation

The mycelium will now start to colonise the substrate. Depending on the temperature and the frequency of shaking the substrate will be fully colonised in 5-10 days.

A bag of substrate after 3 days. Note the white mycelium

After some days and regular shaking the substrate is fully colonised.

Close up

Casing the substrate

A plastic bin is cleaned with alcohol (note the holes plugged with polyfill). The bags are cut open with scissors.

The fully colonised substrate is put into the bin. Two bags are used for one bin.

The substrate is levelled by hand (wear gloves!) A thin layer (1-1.5cm) of sterilised casing soil is put on.

This too is levelled by hand The bin is covered with polyethylene wrap to prevent contamination and moisture loss.

Side view The bins are now put in a warm place for the casing layer to colonise. After 5 or 6 days the mycelium will show up on the casing layer.

At this moment another bin is put on top (upside down) to create sort of a 'mini-greenhouse'. Note the mesh covered holes in the top bin.

Panaeolus fruiting

After some days the first mushrooms will appear. The casing soil must be kept moist (use a spray bottle). Close up

The mushrooms will mature in a couple of days Fully mature and ready to be picked!

Cultivation notes

Paneolus cyanescens and tropicalis are much more sensitive to high CO2 concentrations. We believe the most important reason for people to fail in their research with Paneolus species is that they do not expose their cultures to enough fresh air. When air exchange is insufficient many mushrooms will form but only a few will mature, the rest will abort. Also the mushrooms appearance is influenced. Improper air exchange will result in tall spindly mushrooms with small caps.

These species will grow in a wide range of temperatures but they really flourish when temperatures are around 25°C or a little higher.

Because not all substrains from a multispore germination seem all to viable it is wise to start with a multispore culture and clone the best looking mushrooms for your further investigations into these two species.

Cultivation of fruitbodies and sclerotia on sterilised grass seed

This document gives instructions on how to prepare substrate suitable for the cultivation of:

Psilocybe mexicana (mushrooms and sclerotia)

Psilocybe tampanensis (mushrooms and sclerotia)

Psilocybe cubensis (mushrooms; rye grain is preferred for this species)

Panaeolus subbalteatus (mushrooms)

Preparation of the substrate

The substrate is based on grass seed. The most commonly sold form is rye grass seed (Lolium perenne) but we have also used mixtures of different species with great success. Make sure however that it is not treated with fungicides. If seed has been treated with fungicides it should say so on the packaging. You may have to look around a little bit to get some unexpensive seed (we buy ours from an animal feed store where it is sold as birdfeeding).

We use the following formula for 720 ml jars

110 grams grass seed

180 ml water

After the water and seed have been filled into the jars, the lids are put on but NOT screwed tight! The lids MUST remain loose! Then a double layer of tinfoil is crumpled over the lid and top part of the jar. Now the jars are ready for sterilisation.

NOTE: Different varieties of grass seed and even batches of the same variety can differ greatly in their ability to absorb water. Too much water results in a slimy clump of seed that cannot be shaken, too little results in substrate that is too dry and produces little or no mushrooms/sclerotia. You should experiment a little with these.

Alternatively you can soak the grass seed overnight in water and then fill the jars with soaked grass seed. This will produce a more homogeneous substrate.

Sterilisation of seeds

The jars should be sterilised in a pressure cooker or autoclave, a normal pot will NOT suffice. First a layer of water is poured into the cooker. The jars are placed in the pressure cooker making sure that the lids are loose! Now sterilise the jars for one hour according to the directions supplied with your pressure cooker. If you are using bigger jars then the sterilisation time should be prolonged. (we sterilise 1.5 litre jars and spawnbags always for 2 full hours). Once the cooker is no longer under pressure the jars should be taken out and the grass seed in the jars should be shaken loose to mix the wet and dry kernels. The jars should then be allowed to cool in a clean place. Always check the jars for cracks before shaking! When the jars have cooled to room temperature inoculations can take place. As the jars are cooling down the lids should remain loose or else they will pull a vacuum.

Inoculation of seeds

When the jars have cooled down they are ready to be inoculated. Don't be hasty, be patient! If you inoculate the jars while they are still hot the spores or mycelium might get killed. You can use a spore syringe, mycelium syringe, agar squares or whatever kind of inoculant you want. The most important thing to remember is to WORK CLEAN! When using syringes always flame the needle before commencing inoculations. When using agar squares always flame the scalpel! Be careful! ALCOHOL AND SPRAY LYSOL ARE HIGHLY FLAMMABLE!!!

Even a simple hood made of a cardboard box prevents prevent drafts and subsequently contamination. Do not expose the sterilised grain to air longer then absolutely necessary. Open the lids of the jars just a crack and work swiftly. After inoculation the lids of the jars are closed and the jars are shaken. Then the lid is loosened again so the mycelium will be able to breathe.

Colonisation of seeds

After inoculation the jars are put in a clean and draft free location. We normally put our jars at room temperature (20°C) or slightly higher. When mycelium starts to grow in only a few spots we shake the jars to redistribute the colonised kernels. This speeds up colonisation dramatically. Depending on the temperature, the species and the method of inoculation the grass seed can be completely colonised in 5-20 days.

When jars are incubated too long or at too high a temperature the mycelium will excrete yellowish metabolites. This situation is not good, these seed in these jars should be cased as soon as possible.

Casing (for the cultivation of mushrooms)

When the grass seed in the jars is completely colonised it needs to be cased. For this purpose we use 1-litre disposable plastic trays. The colonised grass seed of one jar is shaken loose are poured into a tray. If there are lumps within the seed these can be broken up with the clean rim of the jar. The surface of the grain is levelled evenly. Using a big spoon and a fork the grain is now covered with a thin layer (1.5-2.0 cm) of casing soil. We always try to keep the casing surface even while at the same time keeping it rough (with small valleys and hills). The cased tray is then covered with tin foil and put in a clean location (20-25°C). Within a few days you will notice the mycelium growing through the casing soil. Depending on the strain (some strains fruit earlier and easier then others) the casings are now ready to be exposed to air and light to start the fruiting cycle.

Recipe and Preparation of the casing soil for seeds

We use the following recipe:

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 sterilised for one hour in the pressure cooker. When the soil has cooled down to room temperature it's ready to use.

We know that some authors advise against sterilisation of casing soil because it would kill all the beneficial organisms. We however have had only bad experiences with untreated or pasteurised casing soils. We just tell what works best for us!

Fruiting of seeds

Some cultivators use very elaborate set-ups with humidifiers, cool-mist devices and such. We have never found this necessary. The fruiting containers that we use consist of simple clear plastic bins that are covered with polyethylene sheeting. These bins are stackable and thus very space efficient. For air exchange some hole are melted in the sides of the bins. These holes can be covered with mesh to keep out flies. Basically, five cased trays are put in one bin and the evaporation from the casing surface is enough to maintain the proper moisture inside the bin. The holes provide some air exchange. We always cold-shock the harder-to-fruit strains (we put them in the fridge for one night before putting them in the bins). For easy fruiting strains (i.e. Ecuador cubensis) this is not necessary. Psilocybe mexicana, Psilocybe tampanensis and Panaeolus subbalteatus do not benefit from such a treatment. The casings are misted each day and the casing is never allowed to dry out. Directly after a flush is picked watering is increased because the maturing mushrooms pull a lot of moisture from the casing soil. It's very difficult to give explicit directions on a watering regime. You will have to develop a 'feeling' for it. Depending on the strain the first pinheads will appear 6-15 days after putting the casings in the bins. The mushrooms will mature in 5-7 days after which they can be picked. We normally let the casings produce 3 flushes, but they may (when watered properly) produce 5 or even 6 flushes. Psilocybe mexicana usually produces one big flush and a small second flush. Other mentioned species produce more constant.

Keep the surface of the casing as clean as possible by removing dead pinheads (aborts) as these can lead to moulds showing up on the casing surface.

Sclerotia

The mycelium of Psilocybe tampanensis and Psilocybe mexicana can produce sclerotia while still in the jar. Colonised grass seed need not be cased for this to happen. In our experience (with tampanensis) sclerotia will continue to enlarge until 4 months after inoculation. The jars should be put in a clean (preferably dark) location. Sclerotia of these species also form in the casing layer of cased trays.

Making spawn for the woodloving outdoor species

This procedure describes a method of making spawn for the woodloving outdoor species (i.e. Psilocybe azurescens, Psilocybe cyanescens, Psilocybe bohemica).

This spawn can be used to inoculate outdoor beds with woodchips. The creation of outdoor patches is (will be) described in another document.

Procedure

The spawn is based on small woodchips that can be bought in a pet-store. It is used as animal bedding but can also be used to smoke fish and meat. These chips are made from beech. The chips are boiled in water until they sink (approx 1 hour). Alternatively you can soak them in water for some time. Moisture content is right when they sink.

Now drain the chips and let all the loose water run off. Some oatmeal is added to the mixture (approximately one cup for every 3 litre wood chips). This is to boost and speed up mycelial growth. You can also use bran instead of oatmeal.

The oatmeal is mixed in This mixture is filled into autoclavable spawn bags (or jars)

To prevent the bags from blocking the steam valve, a metal lid is placed on top the bags The bags are sterilized for 2 hours in a pressure cooker (for jars 1 hour will suffice)

The bags/jars are cooled down in front of a laminar flow hood

When they have cooled down they can be inoculated from rye grain spawn. Don't use too much as this will give problems when it is placed outside in the beds as grain attracts vermin. We use about 300 ml for one spawnbag

After spawning the bags are sealed with an impulse sealer They are checked for leaks and punctures.

Finally they are shaken and incubated. Depending on the temperature and species used, bags will completely colonise within 2-3 weeks. Bags can be placed at room temperature.

Growing the woodlovers outdoors

Overview of procedure

Spawn is prepared on sterilised woodchips. In the spring the colonised woodchips are used to inoculate more (non-sterile) woodchips in outdoor beds. The beds are covered with plastic and watered on a regular basis. In autumn the plastic is removed and watering is increased. In the late autumn or begin winter the beds will fruit.

Preparation of grain spawn

The preparation of grain spawn is described here. It will not be repeated here.

Mycelium is cultured on agar And transferred to sterilised grain

Growing mycelium on sterilised wood chips

Preparation of the wood chip substrate

Although some people use colonised grain to directly inoculate their outdoor beds this is not the preferred method. The grain attracts all kinds of bugs and rodents. The grain is also more likely to contaminate than properly prepared wood chip spawn.

The woodchips we use are made of beech (Fagus sylvatica) and are sold as animal bedding. We use the smaller size for spawn and the larger as substrate for the beds.

The chips are soaked in water for 48 hours. Don't wait longer than this or fungi may start growing on the wood. The chips are then drained.

Beech wood chips Make sure all water runs off

The soaked chips can be supplemented with something like oatmeal or boiled grass seed to speed up mycelial growth. About one half cup per bag is used.

Bags filled with supplemented wood chips The flaps are folded down, ready for sterilisation.

The bags are placed in the pressure cooker and a rack is put on top to prevent them from blocking the vent pipe.

Four of these bags fit in this cooker The rack on top is very important

Subsequently the bags are sterilised for 3 hours at 121°C and left to cooled down in the flow cabinet.

Sterilise the full 3 hours, don't cut corners Bags cooling down in the flow cabinet

Inoculating the wood chip substrate

The cooled bags are placed in the flow cabinet. The bag is opened taking care not to touch the inside and colonised grain spawn is poured in.

Opening the bag... ...and pouring the spawn in

Now the bag is sealed with an impulse sealer, and the seal is tested. If the bag is leaking at the seal it is sealed again.

Sealing the bags Testing the seal

The strain and date are written on the bag and the bag is shaken to distribute the spawn. The bags are now incubated at 20°C for 3-4 weeks after which they are ready for use.

Making the outdoor bed

For the bed we choose a shaded place surrounded by bushes. First a shallow hole is dug by Cowboy Luuk.

Cowboy Luuk digging a hole

The woodchips that are the same as those used as spawn but they are much coarser (larger particles). The chips are put in bags and these bags are filled with water. The chips are soaked like this for 24 hours.

The hole is filled with drained chips and the spawn is mixed in. A ratio of 1:20 should suffice although higher rates are preferred if the spawn is available.

Colonized wood chip spawn Cowboy Luuk mixing in the spawn

Now the bed is given a final watering and it is covered with a piece of plastic to prevent dehydration.

Keep the bed covered until September

Maintenance

Every week or so you should check to see if the bed is still moist on the inside and water if needed.

Mycelium is clearly visible on the woodchips Close up

Replace the plastic after watering. There will probably be all kinds of insects running underneath but don't worry about them. In September the plastic is removed and the bed is watered on a regular basis to prevent it from drying out.

These will be under the plastic

Once the temperatures are right for the species being cultivated the bed will start to fruit. Do not water the mushrooms unless it's really dry. It helps to live in the neighbourhood of the beds, and not like us, a 2 hour drive away. Usually one or two flushes pop up. In spring next year fresh chips can be added to the beds to promote further fruitings.

Psilocybe subaerigunosa Psilocybe subaerigunosa

Making a sporesyringe

Although the photographs show the procedure in the open air we make all sporesyringes in a flow cabinet!

To make a sporesyringe you will need the following items:

Inoculation loop/scalpel (something to pick up the spores)

Sporeprint

Syringe and needle (sterile)

Small amount of sterilised water in a bottle (capped with tinfoil)

Clean flame source (gas- or alcohol burner)

Latex gloves (optional)

The most important thing in the whole process is to work clean. If possible perform the following procedure in a glovebox or HEPA filtered environment. If you do not have access to one of these you can perform it in the open air, but chances of success or smaller. If available wear gloves that have been disinfected with alcohol 70% or lysol.

CAUTION: Most disinfectants are flammable, use extreme caution when using these in combination with an open flame!

Before you start clean the working surface with alcohol or lysol. Allow it to dry before proceeding! The inoculation loop or scalpel is flamed until red hot, and left to cool. Alternatively you can use a presterilised inoculation loop.

Peal back the tinfoil of the flask so that it can be removed easily but leave it covering the flask. Open the baggie with the sporeprint and scrape some of the spores of the paper. If the loop is too hot the spores will be killed or the plastic will melt to it. Deposit the spores into the water and quickly replace the tinfoil. Repeat if not enough spores have been transferred. If the spores are visible in the water there should be enough.

The syringe is assembled. Most syringes can be reused by sterilising them in a pressure cooker. Just wrap them in tinfoil and sterilise for 25-30 minutes. Some spore suspension is sucked up in the syringe. Pull the plunger back and forth a few times to disperse the spores in the water. Syringes can then be filled with spore suspension.

The needle cap is replaced and the syringes are put in the fridge until ready to use. Don't forget to label them with strain and date. Syringes can be kept like this for several months after which they become noticeably less viable.

Steam sterilisation

The delicate art of pressure cooking

In laboratories worldwide autoclaves are used to sterilise nutrient media, substrates and instruments. Wouldn't it be nice to have an autoclave at home? Autoclaves are expensive, very expensive...... Luckily, an autoclave is really nothing more than a fancy pressure cooker!

Pressure cookers are relatively cheap, easily available and they come in all shapes and sizes. Still they all work on the same principle. The cooker is an enclosed system. Heat turns the water into steam which builds pressure. At higher pressures the boiling point of water rises. At 1,0 kg/cm2 overpressure (= 1 bar) this is 121°C. This is the standard sterilisation temperature.

Always observe and obey the safety instructions that came with your cooker. Never make modifications to it and use only original spare parts. Not doing so may result in an explosion! You have been warned!

Typical sterilisation cycle

Not all cookers work the same. Some need the weight to be placed on from the start on and some don't even have a weight but a spring loaded pressure regulator. For a 'standard' cooker with a weight a typical sterilisation cycle goes as follows, it might be different for your cooker!

A rack is placed in the cooker so that the items to be sterilised are not in direct contact with the bottom.

If items are in direct contact with the bottom of the cooker they might melt (polypropylene) or crack (glass). A simple rack keeps the contents of the cooker 1-2 cm from the bottom and prevents this.

An appropriate amount of water, usually a few centimeters to cover the bottom, is put in the cooker.

An appropriate amount is enough to keep the cooker from running dry but not so much that it takes ages to heat up. A cooker that has run dry is bad news because: A. The contents is ruined B. It stinks up the place C. The cooker will need to be cleaned on the inside D. The metal of the cooker itself may warp When the pressure/temperature is regulated precisely so that no excessive steam escape takes not much water is needed. Of course more water should be added if the contents is sterilised for a longer time. Usually 3-4 centimeters of water on the bottom is enough but this may be different for each cooker/sterilisation regime.

The items to be sterilised are placed in the cooker. For bags a rack is put on top.

Flasks, Jars, bags and instruments are placed in the cooker. Jars and bags can be stacked if the cooker is high enough. When autoclaving bags, a rack is put on top to prevent the expanding bags from blocking the vent pipe on the inside.

The lid is closed and the heat is turned on.

The lid is now placed on the cooker. It is closed by means of rotating the lid or by fastening some wing nuts. The weight, which regulates the pressure, is not put on yet. An electric heating plate or a gas stove may be used. It can be turned to full heat unless it's a really big burner for a small cooker which might lead to the glassware inside cracking.

When a steady head of steam is blowing from the vent pipe the weight is put on.

After some time the water in the cooker will start to boil. Steam will start escaping from the vent pipe. The weight is not placed yet. After a few minutes the steam will flow continuously from the vent pipe and all air that was inside of the cooker is now expelled. This forms a saturated steam environment. The weight is now placed on the vent pipe.

The cooker will start building up pressure.

Since the weight is now blocking the steam flow, pressure will start to rise in the cooker. The rise in pressure corresponds with a rise in temperature. If hissing or leaking is visible the rubber ring that seals the lid to the cooker needs to be cleaned or replaced. The heat is adjusted to keep the weight rocking slowly

When the pressure has reached 1 bar the weight will be lifted by the steam pressure. This releases pressure and the weight will go down again. The temperature is regulated so that the weight keeps rocking and hissing but no excessive steam escape takes placed. As long as the weight is rocking, the contents is at the correct temperature.

After the appropriate time the heat source is turned off.

Sterilisation time is measured from the moment that the cooker reaches 121°C until the moment that the heat is turned off. The cooker is left to cool until the pressure has returned to zero. When the pressure has returned to zero, the cooker can be opened.

Items that can be used when they are cool can be left like this. When the contents has to be used while still hot (agar for instance) or when the cooker needs to be used again as fast as possible the hot content may be removed. Always remove the weight first to ensure that the pressure has dropped to zero before opening the cooker.

The cooker is unloaded and is ready for a new cycle.

The hot items are removed from the cooker with heat insulating gloves. Cold items can be removed bare handed. Sealed bags and jars with a filter can be left to cool anywhere. Agar and unsealed bags are left to cool in a running flow cabinet or improvised inoculation hood.

Sterilising sealed bags

Still many people think that it's impossible to sterilise sealed filter patch bags. They sterilise the substrate in an open bag and seal after spawning. This brings with it a great risk for introducing contaminants into the substrate.

We have had great success with autoclaving sealed filter patch bags, however there are a few things you should know:

The bags expand during cooking which means that if the bottoms of the bags stand in water, they will push the water out of the cooker through the vent pipe. This can be prevented by placing the bags on top of a sturdy rack. The water level should be below the rack. This will mean that there is not much water in the cooker. Pressure has to be regulated precise so no excessive steam escape takes place since that may cause the cooker to run dry.

Since the expanding bags may also block the vent pipe a rack of some sort should also be put on top of the bags to prevent this. If water comes out of the vent pipe this means that there's too much water in the cooker and that the expanding bags are pushing the water out.

The cooker should always be fully filled with bags. If the combined volume of the expanded bags is smaller than the volume of the cooker they will burst. Because the bags will all fully expand during cooking they prevent each other from bursting.

As much air as possible is pushed out during sealing of the bags. This makes it easier to put them in the cooker and allows for better steam buildup. A good impulse sealer must be used, poor seals burst during autoclaving.

Sterilisation time for bags is 1,5 - 2,5 hours depending on the weight of the bags.

After sterilisation the bags are removed and shaken. Shaking is not always possible because many bags will come out with little air inside. This doesn't matter since the bags will inflate during incubation and can then be easily shaken.

Since the bags are sealed now, inoculation can only take place by liquid injection. A (self-filling) syringe is used to inoculate the bags. The injection site is cleaned with an alcohol soaked paper towel and then pierced with the needle. Liquid inoculum is injected into the substrate. The hole is shut with a drop of hot glue from a glue gun.

After the glue has hardened the bags are shaken (if possible) and incubated. Shaking can take place as soon as the bags have inflated (after some mycelial growth, often after a few days.)

Usually bags are fully colonised after 14-20 days.

Sterilising jars

First a rack is put in the cooker, than a layer of water is added. If the cooker permits it the jars can be stacked without a problem. If for some reason jars without a filter are sterilised the lids should not be screwed tight.

Usually bags are fully colonised after 14-20 days.

The jars should never be put directly in hot water or they might crack. After one batch of jars is unloaded, the hot water should be poured out and replaced with cold to prevent this.

Usually bags are fully colonised after 14-20 days.

Jars that can be bought for cheap in the supermarket (containing such delicacies as applesauce or green peas) can be autoclaved two or three times after which they are much more likely to break. They are cheap but might be dangerous when used for too long.

Always treat glass jars with caution, handle them (when unloading and shaking) with thick gloves that protect your hands in the case a jar would break.

Sterilisation time for small jars (500 ml) is 45 minutes, for normal jars (720 ml) 60 minutes and for large jars 90-120 minutes (depending on size).

Sterilising liquids

Liquids such as water and agar are sterilised in bottles or Erlenmeyer flasks. Since agar foams during autoclaving the flasks are never filled for more than 2/3. Bottles with water can be totally filled. The caps of bottles or flasks should never be screwed tight but always left a bit open to prevent im- or explosions.

The following table can be used as a guidance for the autoclave time.

vessel size (ml) sterilisation time (minutes) 25 20 50 25 100 28 250 31 500 35 1000 40 2000 48 4000 63

It's very important that the cooker cools down slowly. When the temperature drops too fast the agar may boil out of it's container which leads to mess.

When agar is sterilised too long it turns dark in color and doesn't gel properly. Sugars are converted to caramel which is toxic to fungi. Care is taken not to let the temperature rise above 121°C for the same reason.

Sterilising other stuff

Items such as scalpel or tweezers can be wrapped in aluminum foil or sealed in tyvek. Most types of syringes are autoclavable as well. These are too wrapped in aluminium foil and sterilised for 15 minutes. Forget about sterilising filled syringe as they will come out of the cooker empty.

MushMush Notes

Preparing Agar

Recipe for Malt Extract Agar (1 liter)

20 grams Malt Extract

2 grams Yeast

15 grams Agar

Water

The dry ingredients are put in a flask and the water is added. This is sterilized for 30 minutes at 121 degrees Celsius.

The flask should be twice as large as the volume of the medium that is sterilized to prevent it from boiling over and should preferably have a narrow opening. The opening is stuffed with polyfill, hydrophobic cotton or capped with Tyvek. This is covered with tinfoil.

Pouring Petri dishes

Condensation on the lids can be prevented by:

pouring Petri dishes when agar has cooled to 40-50 degrees Celsius;

stacking the dishes with warm agar;

putting something hot on the top dish of the stack (a mug with hot water for example).

Dishes should preferably be poured in a glove box or HEPA filtered environment.

Incubation of agar cultures

Petri dishes should be taped around the edges with polyethylene cling wrap. This prevents both dehydration and the introduction of contaminants. A small roll, cut from a big roll with a sharp knife is very useful.

Dishes are Incubated upside down so that droplets of condensation will not fall on the agar surface but will remain on the lid until they evaporate.

Keep track of how often a strain is subcultured. Do not subculture for more than 5 Petri dishes or you will risk losing your strain to degeneration. A sure sign of degeneration is the formation of zones of fluffy mycelium. These cultures should preferably not be used. If there's no choice but to use them, use only the rhizomorphic zones.

Storing cultures

For storage of cultures agar slants are used. The agar is prepared by boiling in a pan and then pouring it into test tubes (a big syringe is useful for this). The tubes are loosely capped and sterilized for 25 minutes in the pressure cooker. The tubes should be taken out before the agar solidifies and put under an angle so that upon solidifying the agar has larger surface for mycelial growth.

The tubes can be inoculated by dropping a small piece of colonised agar into the tube. The tube is loosely capped and sealed with cling wrap. The piece of agar can now be forced downwards onto the agar by tapping the tube it with your hand.

After two weeks of growth the tubes can be put in the fridge where they will remain viable for up to 5 years. Every year tubes are taken out and subcultured in Petri dishes to check if they are still viable. After prolonged storage cultures may show some sectoring (the formation of fluffy zones in the mycelium) so only healthy rhizomorphic mycelium is subcultured.

Making a clean sporeprint

Sporeprints are best taken on a smooth surface that allows easy picking up of the spores with an inoculation loop. Most clean smooth materials will work fine as long as they are clean. Most store bought dry products (paper, tinfoil) that are packaged can be considered clean.

Some strains and species do not easily drop their spores. Often sporulation can be stimulated by increasing the humidity. This is especially important when sporeprints are made from small caps. The caps themselves would dry pretty quickly and once they are dry, they will not deposit any spores.

For species such as Psilocybe mexicana and Psilocybe tampanensis a small plastic container that seals well is used some of the stems of the mushrooms are put in this as well to help raise humidity.

Not all strains drop their spores immediately after the veil tears, so it's best to wait until spores can be seen on the stem near the cap.

The mushroom is picked and put on clean tinfoil. With a sharp knife or scalpel the cap is cut off and the cap is put on the printing medium (paper, tinfoil, Petri dish). The container is closed and after 24 hours the cap is removed. A perfect sporeprint should be the result. Store the sporeprints individually sealed in a ziplock type baggie. These can be stored for years in a cool dry location.

Substrates for Psilocybe cubensis

Almost any type of grain can be used to grow this species on but in our opinion rye grain is the best choice. Other grain types and mixtures do not evenly absorb moisture during sterilization and have to be preboiled.

Rye (in dry form) can be combined with water and then sterilized without the need of preboiling. This saves a lot of time and hassle. When the jars or bags are still hot they need to be shaken to disperse the wet bottom kernels with he dryer top kernels. Upon cooling moisture will spread evenly throughout the substrate and the end result can be shaken easily.

Other grains have to be preboiled in plenty of water. Boiling time depends on the type of grain that is used. Mixtures with small kernels often need less time than those consisting of bigger ones. Kernels that have burst open are not good, and too many of these may give problems with bacterial contamination later on. After boiling the grain is drained and filled into jars or bags. These can then be sterilized.

Substrates for Panaeolus cyanescens and Panaeolus tropicalis

Although literature suggests that pasteurized straw can be used yields are poor compared to using a substrate that contains dung. People have reported good success with pasteurized cow and horse dung. We prefer to sterilized the substrate in spawn bags. A mixture of straw or grass seed and dung seems to work best. Vermiculite can be added to improve structure and water holding capacity.

A high yielding substrate can be prepared with the following recipes:

7 parts dried cow dung

7 parts soaked grass seed Instead of grass seed soaked straw can be used as well

2 parts fine vermiculite

2 parts coarse vermiculite

Ingredients are mixed in dry form (except the soaked grass seed or straw) and water is added until it is saturated. Squeeze out the moisture and sterilised the mixture in spawnbags for 2 hours. These bags can be inoculated from rye spawn.

Incubating bags produce a lot of heat so watch out for overheating of the substrate!

Sterilization time

Substrates can be effectively sterilized by pressurized steam. A pressure cooker or autoclave are perfectly suitable for this purpose.

The required time for sterilization depends on a variety of factors the most important being:

the amount of substrate in one container (bag/jar/flask);

total amount of substrate in the cooker/autoclave;

solid or liquid substrate.

The more substrate is filled into the containers the longer they should be sterilized. Tightly packed pressure cookers require longer sterilization than empty ones. Liquids (agar, water) require briefer sterilization then solids such as rye or birdseed.

Sterilization time is measured from the moment the pressure cooker or autoclave has reached 121 degrees Celsius (1,0 kg/cm2, 15 psi).

200 ml jar rye 40 minutes

200 ml jar grass seed 40 minutes

800 ml jar rye 60 minutes

800 ml jar grass seed 60 minutes

Spawnbag rye (4 liter) 120 minutes

Spawnbag grass seed (5 liter) 150 minutes

Spawnbag dung mixture (3 liter) 120 minutes

Agar slants 25 minutes

Agar (in bottle) 30 minutes

Water (in bottle) 30 minutes

Scalpel, syringes etc. 20 minutes

Large bag casing soil 60 minutes partial sterilization!

Casing soil

Many species benefit from a layer of "casing" soil on top of the colonized substrate. The process of putting such a layer on is called casing.

Recipe:

10 parts peat

5 parts vermiculite

2 parts limestone

The ingredients are mixed in dry form and water is added until the casing soil is almost saturated. The object is to get as much water as possible in without turning it to mud. If too much water has been added some more dry ingredients can be added to compensate.

The casing soil needs to be heat treated before use. Some people have reported success with untreated soils but it seems a big risk to take. There are two practical options: partial sterilization in a pressure cooker and partial sterilization in a microwave.

The wetted soil is put in bag or jars and is 'sterilized' for 1 hour in the pressure cooker or for 25-30 minutes in a microwave at full power. Extra water should be added when a microwave is used.

When it had cooled down the soil is ready to use. If it looks a little dry you can add some clean water to it before applying it to colonized substrate.

The colonized substrate is broken up and poured into trays. The casing mixture is applied and the tray is covered. A normal depth for a casing layer is 1.5-3 cm. Panaeolus cyanescens and Panaeolus tropicalis also need a casing layer but it must be very thin as these species seem to have trouble growing through it.

Sclerotia cultivation

Some species can form so called "sclerotia" in the casing soil and inside of the substrate. Psilocybe mexicana and Psilocybe tampanensis are the two most important species.

Sclerotia are hardened mycelial structures that are formed by the mycelium as a survival mechanism to protect it from floods, forest fires etc. Sclerotia contain 30% dry matter where mushroom only contain 9-10%. Interestingly the sclerotia of the two mentioned species also contain psilocybin and/or psilocin.

Most strains and substrains of these species form sclerotia in the casing soil of cased trays. As a substrate millet and grass seed can be used.

In vitro sclerotia (where the substrate remains in the bags or jars it's growing in) are formed by the "A" strain of mexicana and by some substrains of the Psilocybe tampanensis. Sterilized grass seed seems most suitable substrate. It can be prepared by combining the dry grass seed with water in jars or bags followed by steam sterilization.

Recipe (800 ml jars):

110 grams grass seed

180 ml water

These jars should be sterilized for 1 hour.

Recipe (5 liter spawn bags):

4 liters grass seed

2 liters water

These bags should be sterilized for 2 1/2 hours.

The substrate is inoculated and shaken after a few days. After some time sclerotia will start to form. Tampanensis forms then only against the glass or inner bag surface, mexicana forms them throughout the substrate. After 3 months (mexicana) or 6 months (tampanensis) growth has halted and the sclerotia can be harvested.

Initiation strategy

One the substrate (and casing layer) are colonized it's time to expose the substrate to fruiting conditions. The three most important changes should be:

a drop of temperature by a few degrees Celsius;

lowering of CO2 concentration;

exposure to light for a few hours a day

Not all strains are as sensitive as others. In general the more fleshy and stout strains of Psilocybe cubensis are somewhat more difficult to get to pin than the more slender/thinner strains. Difficult to fruit strains can be 'cold-shocked' by putting the substrate in the fridge for 24 hours before putting them in the fruiting chamber.

Panaeolus cyanescens and tropicalis are very sensitive to high CO2 concentrations (much more than Psilocybe cubensis). If they do not receive enough fresh air, the mushrooms will grow tall and spindly and will abort at an early stage.

If the conditions are not right for the species being cultivated often the mycelium will continue to colonize the casing surface without forming any pinheads. The casing becomes a hard closed surface that will not absorb water. If this happens the casing surface should be scratched open with a clean fork and conditions should be corrected to allow fruiting.

Working with agar

What is agar?

Agar is a polysaccharide found in the cell walls of some red algae from which it's extracted by boiling. This raw agar is then purified.

When agar is dissolved in boiling water and left to cool it will form a gel (very much like gelatin). It can be bought in many different grades from food-grade to purified tissue culture grade.

It's main uses are in the field of microbiology, tissue culture and food preparation (as a vegetarian substitute for gelatin).

Why is agar important?

We use agar as a gelling agent for nutrient media. By adding nutrients (agar itself does not contain digestible compounds) a nutrient base can be made on which mushroom mycelia can be cultivated in a flat two-dimensional way.

It can not be substituted by gelatin since gelatin is digestible and does not gel after autoclaving.

Preparing nutrient medium

There are many recipes that work well but the simplest and easiest to prepare remains:

MEA (Malt Extract Agar):

20 grams light malt extract

2 grams yeast

15-20 grams agar

1 liter water

(Smaller volumes can be prepared by simply using less ingredients in the same ratio)

The dry ingredients are put in a flask (Erlenmeyer or similar) and water is added. Take care not to fill the flask for more than 2/3 of it's volume or it will boil over.

When the water and dry ingredients are put in the flask the opening is stuffed with polyfill or hydrophobic cotton. Another option is to put a piece of Tyvek over it held in place with rubber bands. This allows for the agar to be re-melted in the microwave. A piece of aluminum foil is put on top and the flask is swirled.

The flasks are then sterilised in the pressure cooker at 121°C for 40 minutes.

This medium will support the growth of most saprophytic fungi. Other often used formulations are PDA (Potato Dextrose Agar) and DFA (Dog Food Agar).

When making your own recipes keep in mind that more is not always better. When media are too rich in nutrients mycelium will not grow or grow very poorly secreting yellowish metabolites.

Pouring dishes

When the flasks come out of the pressure cooker or autoclave the temperature of the agar will be close to 100°C. The medium will be liquid until the temperature drops below 40°C. The agar is left to cool until it has almost reached this temperature. As a rule of thumb: If you can hold the bottle in your bare hand for 10 seconds without real discomfort the temperature is right. Do not let it cool too much or it will solidify in the bottle. Better to pour a little too hot than having to reliquify the agar.

Since the lids of the dishes will be removed for a few seconds it's very important to prepare a clean workplace. A laminar flowhood is best but an improvised transfer hood will usually give adequate results.

Whichever is used the table top is cleaned with alcohol or lysol (CAREFUL! THESE ARE FLAMMABLE!) and the dishes are taken out of the tube in which they were packaged and put in stacks of 10 dishes.

When working in less then totally sterile environments it's important to work as fast as possible, limiting the direct contact of agar with outside air.

The flask is swirled to mix the ingredients and the aluminum foil and polyfill are removed.

The lid of the bottom dish is lifted (in fact lifting the lid and the 9 dishes on top). Swiftly a layer of nutrient medium is poured in the dish (to 0,3-0,5 cm depth) and the lid is replaced. Quickly lift the second lid (and the 8 remaining dishes) and work your way up in this fashion.

By letting the agar cool before pouring and by stacking the dishes condensation on the lids is minimized. When a mug or jar with near boiling water is put on the top dish of a stack condensation will be even less.

When the agar in the has solidified the dishes are ready to use.

Preparing agar slants

The normal way to store cultures is in so-called slants. Slants are test tubes in which the agar was cooled on a sloped surface to give the agar a larger surface area.

Slants are prepared a little differently then Petri dishes since the tubes are sterilized with the agar in them opposed to dishes which come pre-sterilized and which are filled with sterilized agar.

The nutrient medium is prepared by bringing the appropriate amount of water to a near boil in a pot on the stovetop. The ingredients are added and the mixture is stirred to let them dissolve. Agar should first be mixed w