This section is from the book "The Gardener's Monthly And Horticulturist V22", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
"We have frequently stated that the chief reason why so many fail in growing mushrooms is because no care is taken to prepare the material first. In the usual way fermentation is too rapid. The Journal of Horticulture gives the following good advice:
" I do not know that I have anything out of the common way to say about the preparation of material for the bed, but I will briefly describe the system. Droppings are collected every morning from the stable litter and placed un an open shed, where they are turned over every day to prevent burning. When there is a sufficient quantity for a bed it is removed to another open shed, where it is allowed to heat a little, and the turning is contiuued for ten days or a fortnight, till it becomes sufficiently dry that it will not bind together much when squeezed in the hand. It is then taken to the mushroom house and made up as firmly as possible to a depth of 11 or 12 inches. The firmness prevents its heating too violently, and consequently drying and exhausting itself, and causes it to retain the heat for a lone: time. It cannot be too firm.. A thermometer is placed in the bed as soon as made, and it is expected in a few days to show a temperature of 85° to 100°. As soon as the heat is declining the spawn is inserted; 95° for a day or two will do no harm, but we must be sure that the temperature is declining, for a higher one would probably be fatal".