Oregon frost dates: F
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Fairview | Mar 16 | Nov 20 | 249 d | 9a |
| Fall Creek | Mar 7 | Nov 27 | 265 d | 8b |
| Falls City | Apr 18 | Nov 7 | 203 d | 8b |
| Fields | May 10 | Oct 7 | 150 d | 6b |
| Florence | Apr 10 | Nov 15 | 219 d | 9a |
| Forest Grove | Apr 16 | Oct 26 | 193 d | 8b |
| Fort Klamath | frost any month | 6b | ||
| Fort Rock | frost any month | 6a | ||
| Fossil | Jun 3 | Sep 14 | 103 d | 7a |
| Foster | Apr 29 | Oct 13 | 167 d | 8b |
| Frenchglen | frost any month | 6b | ||