| Zone Number |
Last Frost Date |
First Frost Date |
| 1 |
June 1 -
June 30 |
July 1 -
July
30 |
| Frost
Potential 365 Days a Year |
| 2 |
May 1 - May 31 |
August 1 - August 31 |
| 3 |
May 1 -
May
31 |
September
1 -
September 30 |
| 4 |
May 1 - May 31 |
September 1 - September 30 |
| 5 |
March 31 -
April 30 |
September
30 - October 31 |
| 6 |
March 31 - April 30 |
September 30 - October 31 |
| 7 |
March 31 -
April 30 |
September
30 - October 31 |
| 8 |
February 28 - March 31 |
October 31 - November 30 |
| 9 |
January 31
- February 28 |
November
30 -
December 31 |
| 10 |
January 31 or before |
November 30 - December 31 |
| 11 |
No Frost |