Frost Dates & Planting Calendars in Colorado
In Colorado, the average last spring frost ranges from April 14 in Grand Junction to June 21 in Edwards, and the average first fall frost from September 7 in Edwards to October 23 in Grand Junction. Pick a city for its full frost-date summary and 42-crop planting calendar.
| City | Last Spring Frost (typical) | First Fall Frost (typical) | Growing Season | USDA Zone |
|---|---|---|---|---|
| Denver | April 30 | October 12 | 165 days | 6a |
| Colorado Springs | May 3 | October 8 | 158 days | 6a |
| Aurora | May 4 | October 8 | 156 days | 6a |
| Fort Collins | May 2 | October 7 | 157 days | 5b |
| Lakewood | May 3 | October 7 | 155 days | 6a |
| Thornton | May 2 | October 11 | 160 days | 6a |
| Westminster | May 2 | October 11 | 160 days | 6a |
| Arvada | May 5 | October 5 | 151 days | 6a |
| Centennial | May 5 | October 8 | 154 days | 6a |
| Pueblo | April 30 | October 9 | 162 days | 6a |
| Greeley | May 2 | October 8 | 159 days | 5a |
| Boulder | May 6 | October 5 | 151 days | 6a |
| Highlands Ranch | May 5 | October 8 | 154 days | 6a |
| Longmont | May 7 | October 5 | 151 days | 5b |
| Loveland | May 10 | October 1 | 142 days | 5b |
| Broomfield | May 2 | October 11 | 160 days | 6a |
| Grand Junction | April 14 | October 23 | 190 days | 7a |
| Castle Rock | May 9 | October 2 | 143 days | 5b |
| Commerce City | May 4 | October 8 | 156 days | 6a |
| Parker | May 9 | October 3 | 145 days | 5b |
| Littleton | May 2 | October 11 | 160 days | 6a |
| Northglenn | May 2 | October 11 | 160 days | 6a |
| Brighton | May 3 | October 7 | 155 days | 5b |
| Dakota Ridge | May 2 | October 11 | 160 days | 5b |
| Englewood | May 2 | October 11 | 160 days | 6a |
| Security-Widefield | May 3 | October 8 | 158 days | 6a |
| Windsor | May 3 | October 6 | 154 days | 5b |
| Ken Caryl | May 2 | October 11 | 160 days | 6a |
| Wheat Ridge | May 5 | October 5 | 151 days | 6a |
| Pueblo West | April 26 | October 13 | 166 days | 6a |
| Fountain | May 3 | October 8 | 158 days | 6a |
| Lafayette | May 2 | October 11 | 160 days | 6a |
| Columbine | May 2 | October 11 | 160 days | 6a |
| Erie | May 7 | October 5 | 151 days | 5b |
| Evans | May 2 | October 8 | 159 days | 5b |
| Louisville | May 6 | October 5 | 151 days | 6a |
| Golden | May 3 | October 14 | 161 days | 5b |
| Clifton | April 23 | October 20 | 179 days | 7a |
| Montrose | April 28 | October 14 | 167 days | 6b |
| Sherrelwood | May 2 | October 11 | 160 days | 6a |
| Durango | May 21 | October 2 | 134 days | 6a |
| Canon City | May 4 | October 7 | 153 days | 6a |
| Greenwood Village | May 2 | October 11 | 160 days | 6a |
| Johnstown | May 10 | October 1 | 142 days | 5b |
| Welby | May 2 | October 11 | 160 days | 6a |
| Sterling | April 30 | October 9 | 161 days | 5b |
| Fort Carson | May 3 | October 8 | 158 days | 6a |
| Lone Tree | May 5 | October 8 | 154 days | 6a |
| Black Forest | May 9 | October 6 | 150 days | 5b |
| Superior | May 6 | October 5 | 151 days | 6a |
| Fruita | April 27 | October 11 | 164 days | 7a |
| Steamboat Springs | June 9 | September 12 | 93 days | 5b |
| Federal Heights | May 2 | October 11 | 160 days | 6a |
| Firestone | May 7 | October 5 | 151 days | 5b |
| Frederick | May 7 | October 5 | 151 days | 5b |
| Fort Morgan | May 6 | October 6 | 153 days | 5b |
| Berkley | May 5 | October 5 | 151 days | 6a |
| Cherry Creek | May 7 | October 8 | 152 days | 6a |
| The Pinery | May 9 | October 3 | 145 days | 5b |
| Castle Pines North | May 9 | October 2 | 143 days | 5b |
| Edwards | June 21 | September 7 | 77 days | 5b |
| Glenwood Springs | May 13 | October 3 | 142 days | 6a |
| Alamosa | May 30 | September 17 | 108 days | 4b |
| Rifle | May 11 | October 4 | 143 days | 6a |
| Gunbarrel | May 6 | October 5 | 151 days | 6a |
When to Plant in Colorado
- Tomatoes
- Peppers
- Eggplant
- Cucumbers
- Zucchini
- Winter Squash
- Pumpkins
- Watermelon
- Cantaloupe
- Corn
- Green Beans
- Peas
- Lettuce
- Spinach
- Kale
- Arugula
- Swiss Chard
- Broccoli
- Cauliflower
- Cabbage
- Brussels Sprouts
- Carrots
- Beets
- Radishes
- Turnips
- Onions
- Garlic
- Potatoes
- Sweet Potatoes
- Asparagus
- Basil
- Cilantro
- Parsley
- Dill
- Oregano
- Thyme
- Sunflowers
- Zinnias
- Marigolds
- Cosmos
- Nasturtiums
- Dahlias