Great suggestions but all still, too academic for me, sadly. Ross, I already have 15 free standing (some stacked) units all around the patio. This one particular wall is only available from about 3 feet up from the floor, leaving about another 3-4 ft. up, to work with. I'm 5'6" and don't want to start standing on stools to reach.
I've got a humongus "Queen of Thorn" plant there and that wall is killing me knowing that I've got room for more, just not sure how to do this.
I just saw Bonsai's thread (again) and those grids might work if I can find someone to drill a couple of nails in.
Thanks again to all for these suggestions.