Abstract: A device for automatically selectively watering plants in a predetermined order for predetermined times comprises a casing which is connectable to a source of water under pressure and which houses a turbine wheel arranged to be driven by the water and to drive a set of gears which form a speed reducer the output shaft of which extends out of the casing and carries a plurality of cams spaced apart along the shaft and each arranged to operate a valve of the pilot-operated type, the valves being identical, juxtaposed in a straight line, and connectable to pipes provided with watering nozzles.