Hi sbreitbart, Are you actually having a problem with Iguanas helping themselves to your TG? If no, I suggest that you don't try and fix a problem until you actually have one. If yes, then you may find the following helpful:
Dealing with Iguanas in the South Florida Landscape
Iguana Deterrent Fence System
Thanks for your advise and yes I have a video of them climbing onto the garden! I am going to go the route of capture.