The fungi agaricus (common button mushroom) cannot be sown in ordinary soil. On the other hand, even when well fertilized, a higher plant such as lettuce will not thrive
in a dark growing room on a mushroom farm. Unlike higher forms of life, mushrooms must find organic matter such as protein and fat vital to their life ready-made in a selective substrate referred to as mushroom growing compost. Various byproducts from other farming operations, such as wheat straw, cotton seed hulls, dried poultry waste, and proteinaceous meals  are blended together to begin the composting process. The mixture is turned regularly to allow
homogenization of ingredients as well as aeration and moisture adjustments within the compost heap. Ricks or rows  are built by specially designed equipment  allowing the grower to control moisture and temperature of the composting process. It takes approximately 28 to 30 days of outdoor composting to prepare for the pasteurization process.
 Ingredients added to
straw to make compost - Urea, Gypsum, Cotton Seed Meal, Cotton Seed Hulls, and DPW