In a really mild winter you could just about be lucky in a sheltered spot, but they are not hardy. If you have no alternative wrap the containers well with bubble wrap as the thing to avoid is the compost freezing. Also best to kee the compost pretty dry over the winter when the planst have gone dormant.
You can try taking a few cuttings - its really rather late to try but you might just be lucky.

Or could you remove them from the containers once they have gone dormant and transfer them to more portable containers which you can transfer to your greenhouse or other frost free place in dry compost? Once the leaves have dropped they won't mind a low light situation.