A method and apparatus for treating a commodity includes a plurality of boxes arranged in two rows with a space formed therebetween. A cover is provided for sealing the two rows of boxes at least along the top surface. A plenum is formed between the two rows of boxes with the plurality of boxes being positioned side-by-side. At least one air handler is positioned to pull air through and/or around the plurality of boxes and through ventilation holes in the boxes and/or through spacers positioned between adjacent boxes and along a length of the space formed between the two rows. The air may be discharged upwardly, horizontally or downwardly therefrom. An even flow of air is achieved between adjacent boxes, through ventilation holes in the boxes and/or through spacers positioned between adjacent boxes and along the two rows of pallets for evenly treating a commodity positioned on the pallets.