This hydroponic device (100) is provided with: a light-blocking culture tank (80) configured so as to accommodate an underground portion (12) of a plant (10)； and a light-blocking partition (50) which is disposed so as to cover a top opening of the culture tank (80) and separates an underground space (12A) in which the underground portion (12) of the plant (10) grows from an above-ground space (11A) in which an above-ground portion (11) of the plant (10) grows. The partition (50) comprises: a fixed member (123) fixed at positions on the culture tank (80), the fixed member (123) having a through hole which surrounds the stem of the plant (10) and remaining in a closed state in which the underground portion (12) of the plant (10) is not exposed to light； and a door member (4) which is attached to the fixed member in a movable state with respect to the fixed member (123), and shifts between a closed state in which the underground portion (12) of the plant (10) is prevented from being exposed to light and an open state in which the underground portion (12) of the plant (10) can be observed.La présente invention concerne un dispositif hydroponique (100) pourvu : d'un bac (80) de culture bloquant la lumière conçu pour recevoir une partie souterraine (12) d'une plante (10) ； et d'une séparation (50) bloquant la lumière qui est disposée de manière à recouvrir une ouverture supérieure du bac (80) de culture et sépare un espace souterrain (12A) dans lequel la partie souterraine (12) de la plante (10) se développe d'un espace aérien (11A) dans lequel une partie aérienne (11) de la plante (10) se développe. La séparation (50) comprend : un élément fixe (123) fixé dans des positions sur le bac (80) de culture, l'élément fixe (123) ayant un trou traversant qui entoure la tige de la plante (10) et restant dans un état fermé dans lequel la partie souterraine (12) de la plante n'est pas exposée à la lumière ； et un élément (4) de porte qui est fixé à l'élément fixe dans un état mobi
