The present invention provides: a method for producing a compost, comprising composting plant-derived organic waste at a weight reduction rate of 95% or more by fermentation treatment, specifically by subjecting the organic waste to fermentation treatment comprising a primary fermentation, which comprises an intermittently agitated fermentation, and a secondary fermentation, which comprises an aerated fermentation, using a microorganism of Bacillus subtilis strain C-3102 (FERM BP-1096) or a mutant strain thereof； the compost produced by the above method； and a method for producing vegetables using the compost.
