Was it similar to this? Make two of them and put them back-to-back. When the plants fill in, it looks like one big plant.

Here is a link that might be useful: Plant Stand

That would probably work. The one I saw had 'holes' to set pots in. they didn't just set on top of a shelf. I can't remember if it was wood or metal, though. The showed it full of vining plants and profusely blooming plants. Was very pretty when all filled in.

Maybe it was a pie stand....or the tomato cages upside down.

try this link maybe its the one you want http://www.wave-rave.com/Idea_Inspirations.aspx#