PURPOSE: To obtain a water culture system capable of growing a desired plant by a desired amount for a desired period by installing a top ventilator controller, an air conditioner and an irrigation controller.

CONSTITUTION: The control over top ventilators 22 for daylighting and light shielding, the air conditioning for obtaining environmental conditions such as a proper temperature and humidity and the control over a water feeder 21 for growing a cultivated plant (irrigation control) are simultaneously or partially carried out. Thereby, the growth of the cultivated plant can be promoted and delayed and the greening by water culture can be performed even in a soilless place.