When to plant in Vernal, UT
USDA Zone 5bEverything below — frost dates, hardiness zone, and what to plant when in Vernal, Utah — is derived from the closest NOAA station with complete climate normals.
In zone 5b, Vernal gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
VERNAL · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Vernal’s own odds, recorded at VERNAL.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Jun 9 | May 23 | May 5 | Sep 13 | Sep 27 | Oct 8 |
| 32°F | May 28 | May 7 | Apr 24 | Sep 23 | Oct 6 | Oct 20 |
| 28°F | May 11 | Apr 25 | Apr 11 | Oct 3 | Oct 18 | Oct 30 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Vernal, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 16 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Vernal planting FAQ
When is the last spring frost in Vernal, UT?
Vernal's average last spring frost falls near May 7 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Vernal, UT?
Expect Vernal's first fall frost near October 6 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Vernal in?
Vernal is in USDA hardiness zone 5b. In zone 5b, winters are cold — pick cold-hardy varieties and protect tender crops.
How long is the growing season in Vernal?
Vernal has about 152 frost-free days — a moderate growing season — between the average last spring frost (May 7) and first fall frost (October 6).
When should I plant tomatoes in Vernal?
For Vernal, sow tomatoes indoors about March 12–March 26 and move the seedlings out around May 14, after the last spring frost.
Never miss a window in Vernal
An email when it’s time to start seeds, transplant, and sow — timed to Vernal’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Green River · 118 km
- Rock Springs · 130 km
- Evanston · 150 km
- Heber · 157 km
- Fruita · 160 km
- Grand Junction · 173 km
- Mapleton · 177 km
- Clifton · 178 km
Frost dates recorded at VERNAL, 1 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Vernal, UT — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00429111. Retrieved from https://blissgarden.com/utah/vernal.