In the Magic Mushroom Growing Kit the substratum consists of rye, rice flour, no cheap fillers like vermiculite and perlite. In a sterile laboratory the development of the spores into the mycelium was done. The only thing to do to grow the magic mushrooms out of this mycelium is to put the growing box in a warm, light, and humid environment. You use both the transparent grow bag and the paperclips for this.