The present invention relates to a mobile device for storing and supplying multiple liquid fertilizers, comprising a housing, enclosing: two or more storage units, each suitable for storing a liquid fertilizer, wherein each storage unit is provided with a storage unit level measurement system, a storage unit filling system and a storage unit venting system; a safety drain liquid fertilizer storage, comprising at least two separate collectors for the separate containment of spilled liquid fertilizer; a dosing and controlling system; and wherein the housing is equipped with a connection for the input of a water flow, at least two connections for the output of liquid fertilizer, and an output for venting gasses. In particular is the invention concerned with a method of storing and supplying liquid fertilizers to a greenhouse, in particular to the fertigation system thereof, using the above described system.