Indiana frost dates: R
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Ragsdale | Apr 9 | Oct 30 | 204 d | 6b |
| Ramsey | Apr 17 | Oct 19 | 185 d | 6b |
| Redkey | Apr 25 | Oct 16 | 174 d | 6a |
| Reelsville | Apr 27 | Oct 15 | 171 d | 6a |
| Remington | Apr 23 | Oct 18 | 178 d | 5b |
| Rensselaer | Apr 23 | Oct 18 | 178 d | 6a |
| Reynolds | Apr 25 | Oct 17 | 175 d | 6a |
| Richland | Apr 12 | Oct 25 | 196 d | 7a |
| Richmond | Apr 24 | Oct 20 | 179 d | 6a |
| Ridgeville | Apr 25 | Oct 16 | 174 d | 6a |
| Riley | Apr 14 | Oct 24 | 193 d | 6a |
| Rising Sun | Apr 23 | Oct 21 | 181 d | 6b |
| Roachdale | Apr 27 | Oct 12 | 168 d | 6a |
| Roann | Apr 26 | Oct 19 | 176 d | 6a |
| Roanoke | Apr 24 | Oct 21 | 180 d | 6a |
| Rochester | Apr 23 | Oct 21 | 181 d | 6a |
| Rockfield | Apr 22 | Oct 17 | 178 d | 6a |
| Rockport | Apr 12 | Oct 25 | 196 d | 7a |
| Rockville | Apr 30 | Oct 12 | 165 d | 6a |
| Rolling Prairie | Apr 19 | Oct 27 | 191 d | 6a |
| Rome | Apr 2 | Nov 7 | 219 d | 7a |
| Rome City | Apr 26 | Oct 21 | 178 d | 6a |
| Romney | Apr 20 | Oct 20 | 183 d | 6a |
| Rosedale | Apr 30 | Oct 12 | 165 d | 6a |
| Roselawn | Apr 29 | Oct 16 | 170 d | 5b |
| Rossville | Apr 21 | Oct 21 | 183 d | 6a |
| Royal Center | Apr 20 | Oct 23 | 186 d | 6a |
| Rushville | Apr 19 | Oct 23 | 187 d | 6a |
| Russellville | Apr 27 | Oct 15 | 171 d | 6a |
| Russiaville | Apr 27 | Oct 18 | 174 d | 6a |