Provided is a method for cultivating low potassium leafy vegetables at high yield without causing growth failure due to potassium deficiency in hydroponics. Cultivation is performed using a hydroponic solution containing a very small amount of potassium in the late cultivation period of low potassium leafy vegetables, thereby keeping the potassium content low at the time of harvest and also allowing the leafy vegetables to be stably harvested at high yield without causing potassium deficiency.
