USDA Hardiness Zone Map

USDA Hardiness Zone      First Fall Frost             Last Spring Frost

               1                                 1Jul - 31 Jul                      1 Jun - 30 Jun

               2                          1 Aug - 31 Aug           1 May - 31 May

               3                          1 Sep - 30 Sep             1 May - 31 May

               4                          1 Sep - 30 Sep             1 May - 30 May

               5                          30 Sep - 30 Oct            30 Mar - 30 Apr

               6                          30 Sep - 30 Oct            30 Mar - 30 Apr

               7                          30 Sep - 30 Oct            30 Mar - 30 Apr

               8                          30 Oct - 30 Nov              28 Feb - 30 Mar

               9                         30 Nov - 30 Dec            30 Jan - 28 Feb

              10                         30 Nov - 30 Dec           30 Jan or before

              11                               Free of Frost throughout the year.