Here’s a guide to help you determine your plant zone. Newfoundland has an incredible range of plant zones. I would water it well going into winter. Also, protect it from the cold. Most plants that die during the winter months do so because they have dry roots that freeze! I think you should probably follow these guidelines that some gardeners in the US use for overwintering roses. University of Illinois Extension has a great guide on preparing roses for winter and using a rose cone, chicken wire with leaves, and mounding soil for winter protection.
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