A paperboard container folded from a single unitary blank of paperboard has a bottom wall, opposite side walls, and opposite end walls. Stacking tabs project from an upper edge of the end walls for receipt in corresponding slots in end edges of the bottom wall of an adjacent stacked container, and ventilation openings are formed in the side and end walls for circulation of air. The end walls are formed by inner and outer roll-over panels, and are slightly inwardly inclined to provide space for circulation of air between the containers when two of them are abutted together in end-to-end relationship. First extension flaps on the ends of the inner roll-over panels lie against and are secured to the inner surface of adjacent side walls, and second extension flaps on the ends of the side walls extend between and are captured by the inner and outer roll-over panels. In a preferred embodiment, the first extension flaps and the roll-over panels are held in place by interengaged detent tabs and slots.