Coalville, UT frost dates
How Coalville compares
- In 8 years out of 10, the last spring frost in Coalville falls between May 21 and June 30, a 40-day window. The first fall frost falls between August 28 and September 27.
- The median last frost is 32 days later than the Utah median of May 10.
- Its 93-day growing season is longer than 4% of the 250 Utah places with a regular frost season (state median 148 days).
- The last frost is 41 days later than the zone 5b median of May 1. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5b chart.
- The weather station records an average of 193 nights a year at or below 32°F.
- Compared with Salt Lake City, UT, 50 km away, the last frost here is 47 days later than there and the growing season is 83 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 21 |
| 50% (median) | June 11 |
| 10% (safe for tender plants) | June 30 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | August 28 |
| 50% (median) | September 12 |
| 90% (late) | September 27 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Coalville, UT
Coalville, UT frost dates — last frost Jun 11, first frost Sep 12, zone 5b. whenisthelastfrost.com
When to plant vegetables in Coalville, UT
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Mar 19 – Apr 2 | May 14 – May 28 | — | — |
| Peppers | Apr 2 – Apr 16 | Jun 25 – Jul 9 | — | — |
| Eggplant | Apr 2 – Apr 16 | Jun 25 – Jul 9 | — | — |
| Tomatoes | Apr 16 – Apr 30 | Jun 18 – Jul 2 | — | — |
| Lettuce | Apr 16 – Apr 30 | May 21 – Jun 4 | May 14 – Jun 18 | Jul 18 – Aug 15 |
| Kale | Apr 16 – Apr 30 | May 14 – May 28 | May 14 – May 28 | Jul 4 – Jul 25 |
| Broccoli | Apr 16 – Apr 30 | May 28 – Jun 11 | — | — |
| Cabbage | Apr 16 – Apr 30 | May 21 – Jun 4 | — | — |
| Cauliflower | Apr 16 – Apr 30 | May 28 – Jun 11 | — | — |
| Okra | Apr 30 – May 14 | Jul 2 – Jul 16 | Jul 2 – Jul 16 | — |
| Basil | Apr 30 – May 14 | Jun 18 – Jul 2 | — | — |
| Peas | — | — | Apr 30 – May 21 | — |
| Spinach | — | — | Apr 30 – May 21 | Jul 18 – Aug 8 |
| Radishes | — | — | May 7 – Jun 18 | Aug 1 – Aug 22 |
| Cucumbers | May 14 – May 21 | Jun 25 – Jul 2 | Jun 18 – Jul 2 | — |
| Zucchini & Summer Squash | May 14 – May 21 | — | Jun 18 – Jul 2 | — |
| Winter Squash & Pumpkins Warning: Your frost-free season is about 93 days, which is tight for winter squash & pumpkins (100+ days). Choose early varieties and use transplants or row covers. | May 14 – May 21 | — | Jun 18 – Jul 2 | — |
| Melons & Watermelon Warning: Your frost-free season is about 93 days, which is tight for melons & watermelon (85+ days). Choose early varieties and use transplants or row covers. | May 14 – May 21 | Jun 25 – Jul 9 | — | — |
| Carrots | — | — | May 21 – Jun 18 | — |
| Beets | — | — | May 21 – Jun 18 | Jul 4 – Jul 18 |
| Potatoes | — | — | May 21 – Jun 11 | — |
| Swiss Chard | — | — | May 28 – Jun 25 | — |
| Cilantro | — | — | May 28 – Jun 18 | Jul 18 – Aug 8 |
| Green Beans | — | — | Jun 18 – Jul 9 | — |
| Sweet Corn Warning: Your frost-free season is about 93 days, which is tight for sweet corn (80+ days). Choose early varieties and use transplants or row covers. | — | — | Jun 18 – Jul 2 | — |
| Sweet Potatoes Warning: Your frost-free season is about 93 days, which is tight for sweet potatoes (100+ days). Choose early varieties and use transplants or row covers. | — | Jun 25 – Jul 16 | — | — |
| Garlic | — | — | — | Aug 29 – Oct 3 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Wanship Dam, UT weather station, 9 km away (elevation 5,942 ft (1,811 m)).
Frost dates near Coalville
- Peoa Jun 11 · Sep 12
- Oakley Jun 5 · Sep 17
- Echo May 30 · Sep 18
- Kamas Jun 5 · Sep 17
- Park City May 29 · Sep 25
- Henefer May 30 · Sep 18
- Croydon May 30 · Sep 18
- Heber City Jun 4 · Sep 20
- Midway May 31 · Sep 11
- Morgan May 25 · Sep 24
Frequently asked questions
When is the last frost in Coalville, UT?
The median last spring frost in Coalville, UT is June 11. There is still about a 10% chance of frost after June 30, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Coalville, UT?
The median first fall frost is September 12, with about a 10% chance of frost before August 28.
How long is the growing season in Coalville, UT?
About 93 days between the median last spring frost and first fall frost.
What planting zone is Coalville, UT?
Coalville, UT is in USDA hardiness zone 5b.