It is big. It's one of the Nancy Jane planters. I was worring about the wind blowing it over, so have never used the bottom layer and sat it in a 24" round tote that's have filled with gravel. Then I put a piece of rebar down the center to hold everything together. I also have a smaller top level that makes it too tall for me to water, so have never used it either. Each planting area is about 11" tall and 11" X11". Not sure if this size is still being sold. Most of them seem smaller. So far, I've never been real satisfied with the results. First year I planted zinnias and lantana, the second year coleus and petunias and last year salvia. Here's a shot from last year. I'm hoping this year with more trailing plants, the plants will cover more of the planter.
This shot is from 2010. The lantana did well but the zinnias didn't look very good.