If you could mount some small eye bolts in the stones near the top to hang strings or wire from, you could have almost any climber/vine. Pole beans, sweet potatoes, cucurbits, climbing roses, or clematis come to mind.
What is your main objective - beauty, usefulness, or the bees? Do you prefer annual or perennial?
I am not a spy. Definitely. Definitely not a spy. Not me. No way. But this tiny ad ...
Permaculture Voices 1, 2 and 3 - all 117 hours of video!