A hardiness zone is a geographic area defined as having a certain range of annual minimum temperature, a factor relevant to the survival of many plants. The Canadian Plant Hardiness Zone map (PHZ Map) system defines 9 zones by long-term average annual extreme minimum temperatures. With 0 having the coldest and 9 the warmest. The zone number designated to each plant species corresponds to the extreme minimum temperatures that plant can withstand. Any plant located in a lower zone then its designation has the potential of not surviving the cold months.
Government of Canada Plant Hardiness of Canada Government of Canada Map Link
Government of Canada Plant Hardiness Zone by MunicipalityView Map