My mom has shepards hooks just "planted" in a large pot of soil (plants at it's feet) and then she has tied it to the rails of the deck. She uses hers for birdfeeders.

GGG

Maybe I'll go the soil route first and see if that is sturdy enough. Our balcony walls are completely solid stucco, so there is nothing to tie anything around. It's become quite a decorating and gardening challenge. Thanks for your suggestion!

Catlike,
Not sure if you went ahead with the shepherd's hook idea; if you didn't would a tripod type of setup work? And with a hanging basket in the center, the foliage and flowers would hide most of the structure.
just a thought....

i was at the nursery this past weekend and saw wrought iron shepherd's hooks on freestanding stands. this was at a nice independent nursery, not a big box store and they carry a large selection of wrought iron items. you might want to check around at some of the nurseries in your area and see if you can find something similar.
here is the nursery that i saw the hooks at, i don't know if they do mail order.

:) jiggreen

Here is a link that might be useful: country market nursery