More Comparing the 2023 map to the previous version from 2012 clearly shows that as climate change warms the Earth, plant hardiness zones are shifting northward. On average, the coldest days of ...

Zone 1 ranges from -60 to -55°F, while Zone 13 ranges from 65°F to 70°F. Each Zone is further split into subsections of 5°F so that you might see the zones mentioned as Zone 1a and Zone 1b.

The 2023 USDA plant hardiness zone map shows the areas where plants can be expected to grow, based on extreme winter temperatures. Darker shades (purple to blue) denote colder zones, phasing ...