A blank includes: a top panel, two side panels, a base panel, a closure panel, and a securing member for closing the erected blank on itself, four sets of corner post panels each extending from a side panel and able to be erected to form corner posts, a receiving portion extending over a portion of the base panel, for receiving the bottom walls of pots, delimited transversely by two intermediate base score lines which define, with the ends of the base panel, two connection/deformation sections on either side of the receiving portion. The intermediate base score lines form two deformable hinges, so that the receiving portion can be moved relative to the ends of the base panel along a vertical axis after formation of the packaging and the pack.