I am more of a farmer, I have a healthy background in science, as it is necessary for the courses I teach elsewhere, but the errors are basically in cultivation.  Home cultivation and growing trops in temperate climes require more than the let nature take its course policy.  If you are growing hemp the conditions for it are very liberal, though the opposite is true of Iboga, The Eyes of the Shepherdess, and other tropical entheogenic plants.  Also as far as cultivating mushroom, there are dangers of contamination and loss of potency with certain drying techniques.  Eventually I will be a full member and be in a position to shed some light, for now I am getting to know this place and see what there is to learn.