Alabama frost dates: O
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Oak Hill | Mar 18 | Nov 11 | 238 d | 8b |
| Oakman | Mar 30 | Nov 4 | 219 d | 8a |
| Odenville | Apr 4 | Nov 1 | 211 d | 8a |
| Ohatchee | Mar 26 | Nov 4 | 223 d | 8a |
| Oneonta | Mar 26 | Nov 10 | 229 d | 8a |
| Opelika | Mar 29 | Nov 5 | 221 d | 8a |
| Opp | Feb 28 | Nov 28 | 273 d | 8b |
| Orange Beach | Feb 28 | Nov 29 | 274 d | 9a |
| Orrville | Mar 21 | Nov 5 | 229 d | 8b |
| Owens Cross Roads | Apr 4 | Oct 30 | 209 d | 8a |
| Oxford | Mar 23 | Nov 9 | 231 d | 8a |
| Ozark | Mar 1 | Nov 24 | 268 d | 8b |