Earthworms are used in the vermiculture process to turn organic waste into the most nutrient-dense fertilizer (from the Latin vermis, meaning "worm"). The microbes and minerals found in worm manure, also known as vermicompost or worm castings, are crucial for healthy plant growth, root development, and disease prevention. Farmers and gardeners refer to worm manure as "Black Gold" because just one tablespoon can support a small plant for three months.