it not picky, as long as it has air, infact typically i like to either age in the final pots they are gonna be in or age the soil on a tarp.Hello RIU. Im about to purchase the last ingredients and begin 'cooking' my soil. My question is does the container have to be black and does it have to be a garbage can??? Can i use a rubbermaid or something along those lines. Peace and thanx.