PROBLEM TO BE SOLVED: To provide a technique of cultivating plants for reducing a water replenishing cost. SOLUTION: This technique of cultivating plants is such that a greenhouse 12 includes a dehumidifier 40 which separates water from air in the greenhouse 12, and water supplying means 50 which supplies water obtained from the dehumidifier 40 and water obtained from a fuel cell 11 to a plant 15 and soil 54. Since water is thus separated from the air in the greenhouse and supplied to the plant and soil, the replenishing amount of water is reduced. When the amount of water supplied from the outside of the greenhouse is reduced, heat energy used for heating the water is reduced, and as a result, the technique of cultivating plants having high energy efficiency is provided. COPYRIGHT: (C)2011,JPO&INPIT
