Frost dates for 84329Park Valley, UT
The average last spring frost in Park Valley is May 21 and the average first fall frost is October 2, giving a typical growing season of about 132 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 21
- Average first fall frost
- Oct 2
- Growing season
- 132 days
Safer after Jun 11 (1-in-10 risk)
Possible by Sep 17 (1-in-10 risk)
Last frost typically in 206 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 18 · Jun 4 · Jun 21 | Sep 8 · Sep 24 · Oct 7 | 109 days | 100% |
| Frost / freeze (32°F) | May 2 · May 21 · Jun 11 | Sep 17 · Oct 2 · Oct 17 | 132 days | 100% |
| Hard freeze (28°F) | Apr 16 · May 3 · May 25 | Sep 27 · Oct 12 · Oct 27 | 161 days | 100% |
Planting calendar for Park Valley
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 20 – Jun 26 |
| Tomatoes | Transplant outdoors | Jun 6 – Jun 12 |
| Peppers | Start seeds indoors | Apr 20 – May 21 |
| Peppers | Transplant outdoors | Jun 20 – Jul 21 |
| Eggplant | Start seeds indoors | May 7 – Jun 5 |
| Eggplant | Transplant outdoors | Jun 20 – Jul 21 |
| Cucumbers | Sow outdoors | Jun 20 – Jun 22 |
| Summer squash | Sow outdoors | Jun 6 – Jul 21 |
| Winter squash & pumpkins | Sow outdoors | Jun 20 – Jul 21 |
| Snap beans | Sow outdoors | Jun 6 – Jul 15 |
| Sweet corn | Sow outdoors | Jun 6 – Jun 12 |
| Watermelon & cantaloupe | Sow outdoors | Jun 20 – Jul 21 |
| Okra | Sow outdoors | Jun 13 – Jul 6 |
| Peas | Sow outdoors (spring) | Apr 20 – Jun 5 |
| Potatoes | Plant outdoors (spring) | Apr 20 – Jun 20 |
| Onions | Start seeds indoors (spring) | Mar 9 – Apr 5 |
| Onions | Transplant outdoors (spring) | May 7 – Jun 5 |
| Broccoli | Start seeds indoors (spring) | Apr 2 – May 6 |
| Broccoli | Transplant outdoors (spring) | May 7 – Jun 5 |
| Broccoli | Start seeds indoors (fall) | Jun 2 – Jun 12 |
| Broccoli | Transplant outdoors (fall) | Jul 2 – Jul 13 |
| Cabbage | Start seeds indoors (spring) | Mar 23 – Apr 20 |
| Cabbage | Transplant outdoors (spring) | Apr 20 – May 21 |
| Cabbage | Start seeds indoors (fall) | May 23 – Jun 22 |
| Cabbage | Transplant outdoors (fall) | Jun 22 – Jul 23 |
| Leaf lettuce | Sow outdoors (spring) | Apr 20 – Jul 6 |
| Leaf lettuce | Sow outdoors (fall) | Jun 22 – Aug 8 |
| Spinach | Sow outdoors (spring) | Apr 13 – May 27 |
| Spinach | Sow outdoors (fall) | Jul 9 – Aug 13 |
| Radishes | Sow outdoors (spring) | Apr 20 – Jun 10 |
| Radishes | Sow outdoors (fall) | Jun 22 – Aug 23 |
| Kale | Sow outdoors (spring) | May 7 – May 27 |
| Kale | Sow outdoors (fall) | Jun 15 – Jul 23 |
| Carrots | Sow outdoors (spring) | May 21 – Jul 6 |
| Carrots | Sow outdoors (fall) | May 23 – Jul 8 |
| Garlic | Plant outdoors (fall) | Sep 22 – Oct 23 |
Where these dates come from
ZIP code 84329 is matched to the NOAA station Rosette, UT, 6.8 km away, at 5,685 ft elevation (588 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Rosette, UT (used) | 5,685 ft | May 21 | Oct 2 |
| Grouse Creek, UT | 5,320 ft | Jun 4 | Sep 17 |
| Malta 4 Ese, ID | 4,590 ft | Jun 1 | Sep 19 |
| Malta, ID | 4,521 ft | Jun 5 | Sep 13 |
Frost dates near Park Valley
- Almo, ID 83312 · last Jun 4, first Sep 17
- Malta, ID 83342 · last Jun 5, first Sep 13
- Grouse Creek, UT 84313 · last Jun 4, first Sep 17
- Snowville, UT 84336 · last May 22, first Sep 20
- Oakley, ID 83346 · last May 15, first Oct 2
- Albion, ID 83311 · last Jun 5, first Sep 13
- Holbrook, ID 83243 · last May 22, first Sep 20
- Declo, ID 83323 · last Jun 5, first Sep 13
Frequently asked questions
- When is the last frost in Park Valley, UT?
- For ZIP code 84329, the average last spring frost (32°F) is May 21, based on NOAA 1991-2020 climate normals for the Rosette, UT weather station. There is a 1-in-10 chance of a frost after June 11.
- When is the first frost in Park Valley, UT?
- The average first fall frost (32°F) is October 2. There is a 1-in-10 chance of frost by September 17, so tender plants are at risk from that point on.
- How long is the growing season in 84329?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 132 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.