Outdoor mushroom cultivation

This guide is provided for informational and educational purposes only. We do not encourage you to break the law and cannot claim any responsibility for your actions.

This preparation is intended to be a general outdoor cultivation guide that can be applied across many species. This is for informational purposes only. It is up to an individual to understand the laws in their area concerning mushroom cultivation.

Not all mushrooms need to be grown indoors. Mushrooms were around far before anyone even thought about contamination and many species did just fine.

Basically, a grain spawn is prepared, pasteurized, or sterilized. Substrate is inoculated with this grain spawn indoors and then the colonized substrate is used to inoculate an outdoor substrate bed located in a shady spot. If the bed is kept moist, a fruiting will occur within as little as three weeks. However, it often can take quite a bit longer so patience is key.

Materials

Colonized Spawn

100% colonization is necessary regardless of the original spawn. A simple way to do this can be found here.

Substrate

Dry materials are easier to transport, but hot soaking straw or manure in a pot or Rubbermaid bin (so that it is pasteurized, eliminating competition from other fungus and mold) is a good idea. It is possible to use unpasteurized straw or manure and hydrate on site, but it is not recommend.

Adding sterile vermiculite to some substrates can "fluff" it up and keep it aerated to avoid unwanted anaerobic molds from growing.

Wood Chips

Some species of mushroom can be grown in wood chips and are sometimes known as "wood lovers." Examples of some wood lovers are Psilocybe cyanescens, Psilocybe azurescens, Psilocybe subaeruginosa, Psilocybe bohemica, Psilocybe arcana, and Psilocybe serbica. All of the wood loving species follow essentially the same cultivation requirements. Sterilized wood chips are inoculated with grain spawn indoors and then the colonized wood chips are used to inoculate an outdoor wood chip's bed located in a shady spot.

Cow/Horse Manure

An animal with a proper digestive system is needed, so cow and horse manure are the most popular choices (although a few other types are possible such as deer, rabbit and elephant). A human vegetarian's waste will not work, so please do not try. You can acquire manure from a hardware store or plant nursery. Test a small amount to see if it will work for you and make sure it doesn't have fungicide listed on the bag. Some brands may work better than others.
If this is not possible, you may acquire and use a natural source so long as your dung is treated properly.

Sourcing

You may source this in riding stables, farmyards, or parks. Try to acquire your substrate in the warmer months and stock up for the wet season as old half-dried is best. Sometimes your local police might have horses and you may ask them for some for your flowers. Keep in mind that depending on what you look like, the police may be suspicious if you do not look like a person that grows flowers. Again, horse and cow manure are preferred.

You will need several small and flexible bags as well as one opaque, heavy duty bag.
A small bag is placed over the hand and is used to pick up the material. It is turned inside out on itself so that the material is now inside the bag and your hand is outside the bag.
Place the smaller bag in the larger bag.
Repeat as necessary.

Manure is great for growing many other types of plants like roses and vegetables.

Leaching and Drying

The following is a guide for a fresh source:

If a person has acquired fresh dung, it will need to be leached (soaking out the ammonia). It can be dried as well. One does not need to trouble themselves with older manure as it will have most likely been leached by the rain.

Gloves are suggested for the below steps.

Pick off any rocks and foreign matter, regardless of the age of the material
Soak the manure in water for about 24 hours.
Drain well.
When the material is dry, regardless of age, you can store it or use it immediately.

A person can dry it out on a tarp, in the sun or air, or even using a box with a fan. Do not use an oven.
It's a good idea to break the material up as it dries to check moisture level inside and speed up the drying process.

_{Skipping the drying stage is possible.}
The material must be free of ammonia and ideally completely dried out. Again, aged is easier as it (commonly) doesn't need anything done to it. The older stuff is easier to pick up and is also often full of a friendly white bacteria. Aged dung starts to turn white and very fresh dung dries brown/green. The white is the bacteria (firefang (actinomyces)) and is useful. Where the material is white, it is strongly established.

Preparing for spawning

Pasteurization is heat treatment applied to a substrate to destroy unwanted organisms while keeping the favourable ones alive. The temperature range is 60°C to 80°C. The treatment is very different from sterilization, which aims at destroying all organisms in the substrate. You should usually heat (but not boil) for 90 minutes or so.

Sterilization is completely destroying all micro-organisms present by heat (autoclave, pressure cooker) or chemicals. Spawn substrate always has to be sterilized prior to inoculation.

Mix the leached dung (dry or wet) into your desired recipe and pasteurize it. Add some vermiculite if it's too runny.
Manure probably needs to be mixed with straw (a great additive to a horse/cow manure mix) to "fluff" it up and give the substrate more aeration and paths for myc to colonize along. It may not be necessary to do this with horse material, but many growers will use a straw/dung mixture, using anywhere along the spectrum of 99% straw - 99% manure. The recommended is 90% straw. A person can pasteurize the manure together with the straw if that is their preference.
After pasteurising, drain, squeeze, and drain more. "Fluff" it up and mix it with spawn. Some compression may be a good idea for this stage.
Let it all colonize, just as if you just mixed spore solution into the substrate in your jars. 100% colonization is your goal.

Straw

Other Equipment

Rubbermaid bin or a large stock pot
Mesh bag or pillow case

Setting Up

Area

You will first need to pick out an appropriate area; a remote location is usually best. A shady area is ideal, but the garden will benefit from a small amount of light at least once in the day. Avoid pine trees as best as you can because their soil generally contains unwanted acids. However, pine is not necessarily fatal to the process.

Make sure this layer has sufficient air, but is not packed too loose. Cover all the ground so it is a solid patty. Pine is sometimes, but rarely, the preferred location for some mushrooms. Try to pick an area that will drain well if there is heavy rain. Outdoor fungi growing is best achieved when and where the weather is between 50 and 90 degrees with relatively high humidity. Location on the planet and the time of year will have a lot to do with success rates.

Procedure

Grow Box

This tek will cover outdoor cultivation, however, it does assume you already have colonized substrate jars.

Garden Patch