To calculate the volume you multiply Length times Height times Width. This will give you the cubic foot measurement. You can purchase bags of soil in 1 or 2 cubic foot packages. One cubic foot, nearly 26 dry quarts, will fill 2 to 3 one-gallon containers, depending upon how high you make the soil level and the size of the roots of the particular plants you will put into the container. The most economical way to fill so many large containers would be to purchase your potting soil in bulk rather than in packages. |