PROBLEM TO BE SOLVED: To provide a method for cultivating a plant and a device for cultivating a plant, for promoting growth of the plant in hydroponic culture. SOLUTION: In this method for cultivating a plant by the hydroponic culture using a culture solution, light in a wavelength range in a visible region is irradiated to a root region of the plant. Preferably, the light is reddish lightαwherein a wavelength [nm] is in a range of 600-750, bluish lightβwherein a wavelength [nm] is in a range of 435-500, and/or yellowish lightγwherein a wavelength [nm] is in a range of 570-600. COPYRIGHT: (C)2013,JPO&INPIT
