In a solution cultivation method for a low potassium vegetable, an entire cultivation period from seeding to harvesting is divided into a first cultivation period and a second cultivation period depending on the vegetable to be cultivated. In the first cultivation period, the vegetable is cultivated in a first culture solution containing a first fertilizer for solution cultivation which contains potassium. In the second cultivation period, the vegetable is cultivated in a second culture solution containing a second fertilizer for solution cultivation which does not substantially contain potassium. During the second cultivation period, an air flow is applied at a controlled speed to the growing point of the vegetable.