Cultivating the Psilocybe cubensis on a substrate of rye, covered with a casing layer is one of the easiest and thus one of the most frequently used methods. All strains of the cubensis grow very well on a substrate of only rye covered with a casing layer.
To cultivate cubensis on rye you need the following:
- spore syringe
- tray or box
- pressure cooker
The amounts for substrate ingredients are (by volume):
1 part rye
0.7 - 0.9 part water
The rye, which will serve as substrate, has to be sterilized first. To sterilize rye you need to mix it with water. A often-used ratio is 1 part rye, 0.8 part water. When you use larger amounts of rye for in a filter bag less water is added otherwise it will become a sloppy substance. With only half filled standard jars you can use some more water. The general rule is: more rye is less water.
A full jar has to be sterilized at 15 psi for one hour. A full filter bag has to be sterilized at 15 psi for two full hours.
Keep in mind that the rye absorbs the water. So the rye grows during the process of sterilization. Especially when using jars to sterilize rye, it is important not to fill them up too much. The rye needs space. Also, it's good to have some space left in the jar so you can shake it well. When the rye has been sterilized and when it's still warm, it needs to be shaken well.
This way the rye and the wet crumbs get the chance to mix about. After a good shake leave the rye to cool off, to about room temperature.
When the sterilized rye has cooled off and has reached room temperature, it's ready to be inoculated. Open the jar and inject some spore water. Close the jar steady and quickly. After inoculation shake the jar or filterbag well, so all the spores are spread through the entire substrate. Basically your job is done for now. The spores need time to grow into mycelium. Put it away in a dark and warm spot of approximately 28-30 degrees C.
Usually you will see small white dots appear after a few days. This is the start of the growth. After 2-4 weeks the entire substrate will be coloured white. The speed of growth of the mycelium is highly dependable on the warmth and the quantity of spores in the substrate. It can considerably improve the growing-speed to shake the jars well every 4-5 days. This keeps the rye and mycelium loose and crumbly.
Once the substrate is completely colonized, it's time to cover the mycelium with a casing layer. First shake the mycelium till it is completely loosened up. This can be a difficult task because of the rye that forms tough lumps of mycelium. Watch out not to break the jar.
Thoroughly clean the box you want to choose for growing the mushrooms. Open the jar and scatter the rye over the box. The next thing to do is to add the casing layer. The depth of the casing layer has to be around 1 - 1.5 centimeter. Take care that the casing layer is completely flat. Finally cover it with a lid.
Put the box back in the incubation room for a couple of days. You have to give the mycelium some time to grow through the casing layer. Make sure to close the box properly so the humidity remains as high as possible, close to 100 %.
When you notice the white mycelium covering about 20-30% of the surface, it's time to expose it to the fruiting conditions. Do this by exposing it to light, fresh air and a lower temperature. After about a week the first pins will emerge from the casing. From this point the whole process will go considerably faster.