A composting box includes a main unit and one or two detachable side panels. In a preferred embodiment, the main unit includes two spaced apart main walls attached at diagonally opposite corners with connecting and spacing members. Each of the detachable side panels is adapted to attach to a side of the main unit. After detaching the side panels, the main unit can be separated from a compost pile. The compost pile is then easily re-transferred back into the main unit, and the side panel(s) reattached. This method provides an inexpensive, labor-saving way to maintain and periodically aerate compost piles.