The Garden Bug: Know your zone
By Brenda Weaver
The USDA maintains a clickable public website that provides the expected lowest temperatures of all the geographic areas of the U.S. at: https://planthardiness.ars.usda.gov/pages/view-maps
It is used by gardeners and growers to determine which plants can be grown in each of the "zones" and be likely to survive the winter there.
Source: United States Department of Agriculture
NOTE: Canada has plant hardiness information here: http://planthardiness.gc.ca/