If they are similar to Earthboxes, there is a hole in the side for overflow. You just fill them until water comes out that hole. You need to water everyday once your season gets going and try to determine how rapidly the reservoir empties out. The top of the soil mix should always be moist.

If they are Earthboxes, they hold about 15 gallons or 2 cubic feet of mix. The EB people say you can grow 2 tomatoes, or 2 zucchini or 6 cucumbers in one of their pots. If your tomatoes are large indeterminates, you'd probably be better growing only one. And I don't think anyone needs more than one zucchini plant. But that's just my opinion.

Edit: Sorry. I see you wanted to grow peppers, not cucumbers. You could grow two of those.

This post was edited by Ohiofem on Sat, May 17, 14 at 12:10