This is not an easy question since there are so many different pot configurations. Roughly speaking - very roughly, I might add -- an 8-inch pot probably has a gallon of growing media. If you are planning on mixing it with a premium plant food like Osmocote, you'll want to add 12 grams of fertilizer (about 1/2 an ounce). To place that into perspective, a 1 LB. bottle of Osmocote contains, 32 half-ounce granules. Keep growing, Marianne Binetti