Zone 1
below -85 degrees F

Zone 2
-40 to -30 degrees F

Zone 3
-40 to -30 degrees F

Zone 4
-30 to -20 degrees F

Zone 5
-20 to -10 degrees F

Zone 6
-10 to 0 degrees F

Zone 7
0 to 10 degrees F

Zone 8
10 to 20 degrees F

Zone 9
20 to 30 degrees F

Zone 10
30 to 40 degrees F

Zone 11
Above 40 degrees F