Wow, I almost hate to interrupt your thought processes.
Thanks for the question and the Tree-mail; I'll just answer here if that's okay.
Leaves of okra are very variable and it's difficult to be sure.
Leaves of the Hibiscus sabdariffa/Roselle are also variable.
With the red stems and veins it could be a burgundy okra or might even be a Hibiscus sabdariffa.
There are a few other things it could be, but the person who gardened in that spot last year must have thought it was worth growing.
If you have time and can spare the garden space why not let it grow until the mystery solves itself.
Keep posting photos as it grows!
