Abstract: A method and an apparatus are provided for inserting labels into blow-molded hollow articles. The blow-molding apparatus includes a carrousel mounted to rotate within a support frame. The carrousel carries four multi-cavity molds around a circular mold path. Two blow-molding workstations are disposed next to the mold path in fixed positions relative to the frame. The carrousel is indexed to cause each mold to pause by each workstation, and at a label-insertion station, one time during each carrousel revolution. An in-mold labeler inserts a label into each mold at the label-insertion station. The in-mold labeler includes four picker heads supported on a carriage that shuttles the heads between label dispensing magazines and the mold station path. Each magazine includes a label stack receptacle in which labels rest edgewise, by gravitational force on a pair of label guide surfaces.