If it is in full sun and well drained soil, that is you added lots of gravel around it to help with drainage then, it should be OK. It is the wet winter weather that causes real problem, solve that and it will be fine.

I have had one for a good few years now, I have never protected it in the winter, and officially the temperature has been down to minus 22deg c, and where I am you can add another few degrees to that, with the milder winter 2011-2012 it actually flowered about a month later than it did in the cold winters we had in the 2 previous years, so yes they are pretty hardy, and the bigger they get, the hardier they get, Derek.