The present invention provides a spill-resistant air freshener canister that includes: a supply vessel filled with aromatic liquid that has a threaded mouth sealed with a puncturable membrane; a cylindrical inner sleeve incorporating a socket that sealably engages the threaded mouth of the supply vessel, the sleeve also having a cylindrical axial aperture at the bottom of the socket, and at least one seepage aperture at the very bottom of the socket which enables liquid from inside the supply vessel to escape in a radially outward direction to the exterior of the cylindrical sleeve; a cylindrical wick surrounding the cylindrical inner sleeve; and a evaporator cage into which the cylindrical sleeve is inserted, the evaporator cage having a fully-enclosed bottom portion containing a central projecting blade that fits through the axial aperture at the bottom of the socket. The bottom portion is ultrasonically welded to the bottom of the cylindrical inner sleeve.