Compost

Etymology
From

Noun

 * 1) The decayed remains of organic matter that has rotted into a natural fertilizer

Verb

 * 1) To produce compost, let organic matter decay into fertilizer

Thesaurus
admixture, ammonia, castor-bean meal, commercial fertilizer, commixture, composite, compound, dressing, dung, enrichener, fertilizer, fusion, guano, immixture, interfusion, intermixture, manure, mix, muck, night soil, nitrate, nitrogen, organic fertilizer, phosphate, superphosphate