A blank of sheet material for forming a polygonal container is provided. The blank includes a bottom panel, two opposing side panels, and two opposing end panels. Each side panel extends from a side edge of the bottom panel, and each end panel extends from an end edge of the bottom panel. Each end panel includes at least one major stacking extension extending from a top edge thereof. The blank further includes a reinforcing panel assembly extending from a first side edge of a first end panel of the two end panels. The reinforcing panel assembly includes an inner end panel having a minor stacking extension extending from a top edge thereof. The minor stacking extension is configured to align with a respective major stacking extension to form a stacking tab.