Rokunojo 六農醸 means using natural yeast to cultivate the sake. As such, the mash takes about 2 months to be completed which is 5 times longer than the usual starter mash. 
 
The unique aroma of Kumamoto No. 9 yeast, the inherent sweetness of Yamadanishiki Rice with the natural yeast creates a flavour that has a gentle taste when put in the mouth, followed by a subtle wild flavour that adds depth and resulting in a very delicate sake.