Frost dates for 84526Helper, UT
The average last spring frost in Helper is May 3 and the average first fall frost is October 12, giving a typical growing season of about 160 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 3
- Average first fall frost
- Oct 12
- Growing season
- 160 days
Safer after May 21 (1-in-10 risk)
Possible by Sep 29 (1-in-10 risk)
Last frost typically in 188 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | May 3 · May 18 · Jun 5 | Sep 21 · Oct 2 · Oct 16 | 136 days | 100% |
| Frost / freeze (32°F) | Apr 20 · May 3 · May 21 | Sep 29 · Oct 12 · Oct 25 | 160 days | 100% |
| Hard freeze (28°F) | Apr 8 · Apr 22 · May 8 | Oct 8 · Oct 22 · Nov 5 | 180 days | 100% |
Planting calendar for Helper
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Apr 2 – Jun 8 |
| Tomatoes | Transplant outdoors | May 19 – Jun 22 |
| Peppers | Start seeds indoors | Apr 2 – May 3 |
| Peppers | Transplant outdoors | Jun 2 – Jul 3 |
| Eggplant | Start seeds indoors | Apr 19 – May 18 |
| Eggplant | Transplant outdoors | Jun 2 – Jul 3 |
| Cucumbers | Sow outdoors | Jun 2 – Jul 2 |
| Summer squash | Sow outdoors | May 19 – Jul 3 |
| Winter squash & pumpkins | Sow outdoors | Jun 2 – Jul 3 |
| Snap beans | Sow outdoors | May 19 – Jul 25 |
| Sweet corn | Sow outdoors | May 19 – Jun 22 |
| Watermelon & cantaloupe | Sow outdoors | Jun 2 – Jul 3 |
| Okra | Sow outdoors | May 26 – Jun 18 |
| Peas | Sow outdoors (spring) | Apr 2 – May 18 |
| Potatoes | Plant outdoors (spring) | Apr 2 – Jun 2 |
| Onions | Start seeds indoors (spring) | Feb 19 – Mar 18 |
| Onions | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (spring) | Mar 15 – Apr 18 |
| Broccoli | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (fall) | Jun 12 – Jun 22 |
| Broccoli | Transplant outdoors (fall) | Jul 12 – Jul 23 |
| Cabbage | Start seeds indoors (spring) | Mar 5 – Apr 2 |
| Cabbage | Transplant outdoors (spring) | Apr 2 – May 3 |
| Cabbage | Start seeds indoors (fall) | Jun 2 – Jul 2 |
| Cabbage | Transplant outdoors (fall) | Jul 2 – Aug 2 |
| Leaf lettuce | Sow outdoors (spring) | Apr 2 – Jun 18 |
| Leaf lettuce | Sow outdoors (fall) | Jul 2 – Aug 18 |
| Spinach | Sow outdoors (spring) | Mar 26 – May 9 |
| Spinach | Sow outdoors (fall) | Jul 19 – Aug 23 |
| Radishes | Sow outdoors (spring) | Apr 2 – May 23 |
| Radishes | Sow outdoors (fall) | Jul 2 – Sep 2 |
| Kale | Sow outdoors (spring) | Apr 19 – May 9 |
| Kale | Sow outdoors (fall) | Jun 25 – Aug 2 |
| Carrots | Sow outdoors (spring) | May 3 – Jun 18 |
| Carrots | Sow outdoors (fall) | Jun 2 – Jul 18 |
| Garlic | Plant outdoors (fall) | Oct 2 – Nov 2 |
Where these dates come from
ZIP code 84526 is matched to the NOAA station Price Carbon Co Ap, UT, 11.3 km away, at 5,921 ft elevation (88 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Price Carbon Co Ap, UT (used) | 5,921 ft | May 3 | Oct 12 |
| Wellington 3 E, UT | 5,400 ft | May 27 | Sep 26 |
| Scofield Dam, UT | 7,630 ft | Jun 15 | Sep 12 |
| Scofield-Skyline Mine, UT | 8,697 ft | Jun 13 | Sep 17 |
Frost dates near Helper
- Kenilworth, UT 84529 · last May 3, first Oct 12
- Price, UT 84501 · last May 3, first Oct 12
- Wellington, UT 84542 · last May 27, first Sep 26
- Elmo, UT 84521 · last May 18, first Sep 27
- Cleveland, UT 84518 · last May 18, first Sep 27
- Huntington, UT 84528 · last May 18, first Sep 27
- East Carbon, UT 84520 · last May 5, first Oct 15
- Sunnyside, UT 84539 · last May 5, first Oct 15
Frequently asked questions
- When is the last frost in Helper, UT?
- For ZIP code 84526, the average last spring frost (32°F) is May 3, based on NOAA 1991-2020 climate normals for the Price Carbon Co Ap, UT weather station. There is a 1-in-10 chance of a frost after May 21.
- When is the first frost in Helper, UT?
- The average first fall frost (32°F) is October 12. There is a 1-in-10 chance of frost by September 29, so tender plants are at risk from that point on.
- How long is the growing season in 84526?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 160 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.