Limits of the Average Annual Minimum Temperature for Each Zone

Zone 1: Below -50*F

Zone 2: -50*to -35*

Zone 3: -35* to -20*

Zone 4: -20* to -10*

Zone 5: -10* to -5*

Zone 6: -5* to 5*

Zone 7: 5* to 10*

Zone 8: 10* to 20*

Zone 9: 20* to 30*

Zone 10: 30* to 40*