The 12 gallon size is what I ordered. The dimensions on the container are:
15.75 x 15.75 x 11.75 inches
A gallon supposedly takes .13 cubic feet of soil, so 12 gallons should be 1.56 cubic feet (or an 18" cube). This container isn't large enough to hold 12 gallons of soil. If I had to guess, I would say that it is actually an 8 or 9 gallon container.
Not to say that it still isn't going to be overkill.
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