New York frost dates: O
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Oak Hill | Apr 29 | Oct 14 | 168 d | 5b |
| Oakdale | Apr 4 | Nov 11 | 221 d | 7b |
| Oakfield | May 3 | Oct 16 | 166 d | 6a |
| Oakland Gardens | Mar 26 | Nov 25 | 244 d | 7b |
| Oaks Corners | Apr 30 | Oct 21 | 174 d | 6b |
| Obernburg | May 12 | Oct 7 | 148 d | 5b |
| Ocean Beach | Apr 4 | Nov 11 | 221 d | 7b |
| Oceanside | Apr 7 | Nov 8 | 215 d | 7b |
| Odessa | May 10 | Oct 8 | 151 d | 6a |
| Ogdensburg | Apr 29 | Oct 10 | 164 d | 5a |
| Olcott | Apr 26 | Oct 26 | 183 d | 6b |
| Old Bethpage | Apr 6 | Nov 6 | 214 d | 7b |
| Old Chatham | Apr 27 | Oct 14 | 170 d | 6a |
| Old Forge | May 21 | Sep 24 | 126 d | 4a |
| Old Westbury | Apr 2 | Nov 12 | 224 d | 7b |
| Olean | May 7 | Oct 11 | 157 d | 5b |
| Olivebridge | Apr 21 | Oct 27 | 189 d | 6a |
| Olmstedville | May 23 | Sep 27 | 127 d | 4b |
| Oneida | May 1 | Oct 13 | 165 d | 5b |
| Oneonta | May 17 | Oct 3 | 139 d | 5b |
| Ontario | May 1 | Oct 20 | 172 d | 6b |
| Ontario Center | May 1 | Oct 20 | 172 d | 6b |
| Orangeburg | Apr 20 | Oct 26 | 189 d | 7a |
| Orchard Park | May 7 | Oct 11 | 157 d | 6a |
| Orient | Apr 6 | Nov 17 | 225 d | 7b |
| Oriskany | May 1 | Oct 13 | 165 d | 5b |
| Oriskany Falls | May 1 | Oct 13 | 165 d | 5b |
| Orwell | May 10 | Oct 14 | 157 d | 5a |
| Ossining | Apr 25 | Oct 19 | 177 d | 7a |
| Oswegatchie | May 18 | Sep 28 | 133 d | 4a |
| Oswego | Apr 22 | Oct 29 | 190 d | 6a |
| Otego | May 11 | Oct 9 | 151 d | 5b |
| Otisville | Apr 21 | Oct 22 | 184 d | 6b |
| Otto | May 17 | Oct 1 | 137 d | 5b |
| Ouaquaga | May 12 | Oct 9 | 150 d | 5b |
| Ovid | May 1 | Oct 21 | 173 d | 6b |
| Owego | May 5 | Oct 12 | 160 d | 6a |
| Owls Head | May 6 | Oct 4 | 151 d | 4a |
| Oxbow | May 14 | Sep 26 | 135 d | 4b |
| Oxford | May 13 | Oct 4 | 144 d | 5b |
| Oyster Bay | Apr 9 | Nov 10 | 215 d | 7b |
| Ozone Park | Apr 2 | Nov 14 | 226 d | 7b |