Hardiness Zones 101 The USDA Plant Hardiness Zone Map consists of 13 individual zones that take in all of the contiguous United States, plus Alaska, Hawaii, and Puerto Rico. The first zone lies at ...

The importance of hardiness zones lies in their ability to help gardeners and farmers choose plants that will thrive in their ...

Since 1951, Boston has been in planting zone 7a, but the winters here are warming. Our coldest annual temperatures have risen ...