what is worm waste called
Earthworms produce waste called Castings. Castings are excellent fertilizer.   These castings are also known as worm humus or worm manure or, more correctly, vermicast.T â¦ hey are particularly rich in nitrogen, phosphate, calcium, and magnesium.10 people found this useful.arthworms produce waste called Castings. Castings are excellent fertilizer.   These castings are also known as worm humus or worm manure or, more correctly, vermicast.