A hydroponic apparatus (100) includes: a soil surface section (12) including a through-hole (12a) through which to insert a plant (10), and separating a subterranean space (11a) where a subterranean part (10b) of the plant (10) grows and an aerial space (1121) where an aerial part (10d of the plant (10) grows； a growing tank (11), together with the soil surface section (12), forming the subterranean space (11a), where the subterranean part (10b) is placed； germination enhancer supplying units (1000, 2000) supplying a germination enhancer (3), reserved in a germination enhancer reservoir (30), to at least one of the aerial parts (10d, 20d) and the subterranean parts (10b, 20b)； and a control unit (40) controlling a mode in which the germination enhancer supplying units (1000, 2000) supply the germination enhancer (3) to the plants (10, 20).
