Espoma 4 lb. Compost Maker. This 100% bio-organic mix contains microbes cultured for fast, healthy composting. It includes heat active varieties, used to speed the decomposition of difficult materials. It makes composting faster by breaking down hard to compost items. Nineteen elements are considered essential for plant growth. Espoma compost starter is the ideal choice to help make rich, fertile compost nature's original soil conditioner.