What is it?
Cultivated varieties such as shitake and oyster mushrooms provide many nutrients that other vegetables are low in or lack entirely. Most mushrooms species are high in various B vitamins, while others contain an abundance of vitamin C. All mushrooms have ergosterol, a compound called a vitamin D precursor, in their cell walls.
Additionally?
Water is one of four equally important ingredients for composting to work effectively, the other three being carbon, nitrogen, and oxygen. Water, in the right amounts helps maintain activity without causing anaerobic conditions.