Fuente: WIPO "organic farming" A method for manufacturing a nitrogen-enriched organic fertilizer includes a step of treating an organic fertilizer with nitrogen plasma. Further, a method for cultivating a plant includes a step of manufacturing a nitrogen-enriched organic fertilizer by the manufacturing method; and a step of cultivating a plant in soil fertilized with the nitrogen-enriched organic fertilizer. In addition, a method for improving soil includes a step of manufacturing a nitrogen-enriched organic fertilizer by the manufacturing method; and a step of fertilizing the soil with the organic fertilizer. An apparatus for manufacturing a nitrogen-enriched organic fertilizer includes a plasma generation unit; a nitrogen gas supply unit that supplies nitrogen gas to the plasma generation unit; and an organic fertilizer-holding unit that holds the organic fertilizer, in which the organic fertilizer held by the organic fertilizer-holding unit is irradiated with nitrogen plasma generated by the plasma generation unit.