Welcome falcon,
I can't speak to the pomegranate, but like aaron says, wood glue is plenty flexible, and much easier to work with. Cheaper too. I would avoid the silicone glue, as I don't think it will bond properly to either the burlap, or the wood, not like wood glue would. I think you'd be much happier (and safer) using wood glue. If moisture resistance is a concern, use Titebond III.
Frode