Illinois frost dates: G
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Galatia | Apr 7 | Oct 26 | 202 d | 7a |
| Galena | Apr 26 | Oct 15 | 172 d | 5a |
| Galesburg | Apr 20 | Oct 19 | 182 d | 5b |
| Galt | Apr 26 | Oct 13 | 170 d | 5b |
| Galva | Apr 26 | Oct 12 | 169 d | 5b |
| Garden Prairie | Apr 28 | Oct 12 | 167 d | 5b |
| Gardner | Apr 27 | Oct 15 | 171 d | 5b |
| Gays | Apr 16 | Oct 22 | 189 d | 6a |
| Geff | Apr 7 | Oct 26 | 202 d | 6b |
| Geneseo | Apr 20 | Oct 20 | 183 d | 5b |
| Geneva | Apr 25 | Oct 19 | 177 d | 5b |
| Genoa | Apr 24 | Oct 18 | 177 d | 5b |
| Georgetown | Apr 23 | Oct 14 | 174 d | 6a |
| Gerlaw | Apr 22 | Oct 15 | 176 d | 5b |
| German Valley | Apr 26 | Oct 13 | 170 d | 5b |
| Germantown | Apr 6 | Oct 29 | 206 d | 6b |
| Gibson City | Apr 21 | Oct 17 | 179 d | 6a |
| Gifford | Apr 21 | Oct 18 | 180 d | 6a |
| Gilberts | Apr 26 | Oct 18 | 175 d | 5b |
| Gillespie | Apr 14 | Oct 21 | 190 d | 6b |
| Gilman | Apr 25 | Oct 20 | 178 d | 5b |
| Gilson | Apr 21 | Oct 20 | 182 d | 5b |
| Girard | Apr 14 | Oct 21 | 190 d | 6b |
| Gladstone | Apr 8 | Oct 29 | 204 d | 6a |
| Glasford | Apr 16 | Oct 23 | 190 d | 6a |
| Glen Carbon | Apr 4 | Nov 5 | 215 d | 7a |
| Glen Ellyn | Apr 28 | Oct 16 | 171 d | 5b |
| Glenarm | Apr 7 | Oct 29 | 205 d | 6a |
| Glencoe | Apr 26 | Oct 21 | 178 d | 6a |
| Glendale Heights | Apr 28 | Oct 16 | 171 d | 5b |
| Glenview | Apr 26 | Oct 21 | 178 d | 6a |
| Glenwood | Apr 23 | Oct 20 | 180 d | 6a |
| Godfrey | Apr 4 | Nov 5 | 215 d | 6b |
| Golconda | Apr 19 | Oct 20 | 184 d | 7a |
| Golden | Apr 18 | Oct 21 | 186 d | 6a |
| Golden Eagle | Apr 8 | Oct 29 | 204 d | 6b |
| Golden Gate | Apr 7 | Oct 26 | 202 d | 6b |
| Golf | Apr 26 | Oct 21 | 178 d | 6a |
| Good Hope | Apr 17 | Oct 22 | 188 d | 5b |
| Goodfield | Apr 21 | Oct 17 | 179 d | 5b |
| Goodwine | Apr 22 | Oct 19 | 180 d | 6a |
| Goreville | Apr 9 | Oct 22 | 196 d | 7a |
| Gorham | Apr 9 | Oct 22 | 196 d | 7a |
| Grafton | Apr 5 | Oct 27 | 205 d | 6b |
| Grand Chain | Apr 3 | Nov 5 | 216 d | 7a |
| Grand Ridge | Apr 27 | Oct 17 | 173 d | 5b |
| Grand Tower | Apr 9 | Oct 22 | 196 d | 7a |
| Granite City | Apr 4 | Nov 5 | 215 d | 7a |
| Grant Park | Apr 29 | Oct 16 | 170 d | 5b |
| Grantsburg | Apr 14 | Oct 21 | 190 d | 7a |
| Granville | Apr 24 | Oct 17 | 176 d | 5b |
| Graymont | Apr 16 | Oct 24 | 191 d | 5b |
| Grayslake | Apr 24 | Oct 23 | 182 d | 5b |
| Grayville | Apr 7 | Oct 25 | 201 d | 7a |
| Great Lakes | Apr 30 | Oct 19 | 172 d | 6a |
| Green Valley | Apr 16 | Oct 23 | 190 d | 6a |
| Greenfield | Apr 13 | Oct 22 | 192 d | 6a |
| Greenup | Apr 14 | Oct 20 | 189 d | 6b |
| Greenview | Apr 17 | Oct 18 | 184 d | 6a |
| Greenville | Apr 10 | Oct 24 | 197 d | 6b |
| Gridley | Apr 23 | Oct 15 | 175 d | 5b |
| Griggsville | Apr 14 | Oct 21 | 190 d | 6a |
| Groveland | Apr 16 | Oct 23 | 190 d | 6a |
| Gurnee | Apr 30 | Oct 19 | 172 d | 6a |