I can just see a bit of the pointed leaf so that is my clue that this begonia is an Angel Wing or Begonia boliviensis.  There are many new varieties out now and I just an entire series of new Boliviensis begonias at a trial garden put on by growers that showcases the best of new plants. What that means is you will need to experiment as home gardeners discover just how hardy these new begonias will be. I have found that storing the plants in a cool but not freezing dry space for the winter gives the roots a chance to survive and then regrow the following summer. If you do get them to survive the winter, share your experience so we all can learn from you. Keep growing, Marianne Binetti