The present invention is a plant cultivation device (99) that is provided with a cultivation tank (19) that is for growing a plant, with a water tank (30), and with a heat-collecting part (56). The water tank (30) supplies cultivation water to the cultivation tank (19) via an irrigation conduit (38). The water tank (30) also suctions cultivation water from the cultivation tank (19) via a water-sucking pipe (36). The heat-collecting part (56) has an air-storage part (57) that communicates with an upper section of the water tank (30). The heat-collecting part (56) receives sunlight (93), and the pressure of air that is heated inside the air-storage part (57) presses the surface of the water inside the water tank (30). The water tank (30) supplies cultivation water that has been pressed by said air to a culture medium material (90), which is arranged inside the cultivation tank (19), from above via the irrigation conduit (38). The heat-collecting part (56) raises the surface of the water inside the water tank (30) as a result of the heated air being cooled by a decrease in the sunlight (93). The water tank (30) suctions cultivation water from a bottom section (20) of the cultivation tank (19) via the water-sucking pipe (36) in accordance with the cultivation water being raised.La presente invención es un dispositivo (99) de cultivo de plantas que se proporciona con un tanque (19) de cultivo que es para hacer crecer una planta, con un tanque (30) de agua, y con una parte (56) de recolección de calor. El tanque 30 de agua suministra un agua de cultivo al tanque 19 de cultivo mediante un conducto 38 de riego. El tanque 30 de agua también succiona el agua de cultivo del tanque 19 de cultivo mediante una tubería 36 de succión de agua. La parte (56) de recolección de calor que tiene una parte (57) de almacenamiento de aire comunica con una sección superior del tanque (30) de agua. La parte (56) de recolección de calor recibe luz (93) solar, y la presión de aire que se calien
