If the plant in the link below is what you have, you will need to bring it in or take cuttings. It is a tropical plant and cannot take frost.

Cork Screw Hazel will grow in sun or semishade in average soil. There is a disease affecting Hazels that is spreading throughout North America, affected trees have cankers on their bark and branches die. There is no treatment for it other than to cut out the affected branches.

http://www.agf.gov.bc.ca/cropprot/filbertblight.htm

Here is a link that might be useful: Purple Heart

The best place to find a zone map is the National Resources Canada website...

http://atlas.nrcan.gc.ca/site/english/maps/environment/land/planthardi

That should help you :) It's a zoomable map. If you're in the States, I guess go to your country's quivalent website, and hopefully it has something similar!

Good luck with the Corkscrew Hazel, those are beautiful.