Microbial fermentation method for promoting iris japonica dry piece to rapidly generate fragrance

The invention discloses a microbial fermentation method for promoting iris japonica dry piece to rapidly generate fragrance, and belongs to a method for fermenting fragrant plant capable of being aged and generating fragrance. The method comprises the following steps of: mixing 1 percent by weight of strains and iris japonica dry powder to be fermented and 0.01-0.1 percent by weight of a catalyst and the iris japonica dry powder to be fermented by using the pulverized iris japonica dry piece which is naturally fermented for 3-5 years and have good fragrance as strains and using nitrite as the catalyst; and filling the mixed components into a bag to ferment for 15-30 days at the temperature of 30-50 DEG C and the humidity of less than 95 percent. By the method, the aging and fragrance generation time of roots and stems of the iris japonica are shortened, and the production cost of an iris japonica extract is obviously reduced.