A cartridge for an aerosol generating system is provided, including a liquid storage portion including a rigid support portion having a nozzle defining an opening configured to dispense an aerosol-forming substrate and a collapsible portion, attached to the rigid support portion; and a wick disposed in the nozzle, extending across a full cross-section of the opening. An aerosol generating system is also provided, including the cartridge; and a method is provided for forming the cartridge including providing a rigid support portion with a nozzle defining an opening; attaching a collapsible portion to the rigid support portion to form a liquid storage portion; and providing a wick in the nozzle, the wick extending across a full cross-section of the opening.