Frost dates for 84643Mayfield, UT
The average last spring frost in Mayfield is May 11 and the average first fall frost is October 6, giving a typical growing season of about 146 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 11
- Average first fall frost
- Oct 6
- Growing season
- 146 days
Safer after Jun 1 (1-in-10 risk)
Possible by Sep 24 (1-in-10 risk)
Last frost typically in 196 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 11 · May 28 · Jun 14 | Sep 14 · Sep 27 · Oct 8 | 122 days | 100% |
| Frost / freeze (32°F) | Apr 25 · May 11 · Jun 1 | Sep 24 · Oct 6 · Oct 19 | 146 days | 100% |
| Hard freeze (28°F) | Apr 8 · Apr 26 · May 14 | Oct 2 · Oct 16 · Oct 29 | 171 days | 100% |
Planting calendar for Mayfield
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 10 – Jun 16 |
| Tomatoes | Transplant outdoors | May 27 – Jun 16 |
| Peppers | Start seeds indoors | Apr 10 – May 11 |
| Peppers | Transplant outdoors | Jun 10 – Jul 11 |
| Eggplant | Start seeds indoors | Apr 27 – May 26 |
| Eggplant | Transplant outdoors | Jun 10 – Jul 11 |
| Cucumbers | Sow outdoors | Jun 10 – Jun 26 |
| Summer squash | Sow outdoors | May 27 – Jul 11 |
| Winter squash & pumpkins | Sow outdoors | Jun 10 – Jul 11 |
| Snap beans | Sow outdoors | May 27 – Jul 19 |
| Sweet corn | Sow outdoors | May 27 – Jun 16 |
| Watermelon & cantaloupe | Sow outdoors | Jun 10 – Jul 11 |
| Okra | Sow outdoors | Jun 3 – Jun 26 |
| Peas | Sow outdoors (spring) | Apr 10 – May 26 |
| Potatoes | Plant outdoors (spring) | Apr 10 – Jun 10 |
| Onions | Start seeds indoors (spring) | Feb 27 – Mar 26 |
| Onions | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (spring) | Mar 23 – Apr 26 |
| Broccoli | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (fall) | Jun 6 – Jun 16 |
| Broccoli | Transplant outdoors (fall) | Jul 6 – Jul 17 |
| Cabbage | Start seeds indoors (spring) | Mar 13 – Apr 10 |
| Cabbage | Transplant outdoors (spring) | Apr 10 – May 11 |
| Cabbage | Start seeds indoors (fall) | May 27 – Jun 26 |
| Cabbage | Transplant outdoors (fall) | Jun 26 – Jul 27 |
| Leaf lettuce | Sow outdoors (spring) | Apr 10 – Jun 26 |
| Leaf lettuce | Sow outdoors (fall) | Jun 26 – Aug 12 |
| Spinach | Sow outdoors (spring) | Apr 3 – May 17 |
| Spinach | Sow outdoors (fall) | Jul 13 – Aug 17 |
| Radishes | Sow outdoors (spring) | Apr 10 – May 31 |
| Radishes | Sow outdoors (fall) | Jun 26 – Aug 27 |
| Kale | Sow outdoors (spring) | Apr 27 – May 17 |
| Kale | Sow outdoors (fall) | Jun 19 – Jul 27 |
| Carrots | Sow outdoors (spring) | May 11 – Jun 26 |
| Carrots | Sow outdoors (fall) | May 27 – Jul 12 |
| Garlic | Plant outdoors (fall) | Sep 26 – Oct 27 |
Where these dates come from
ZIP code 84643 is matched to the NOAA station Manti, UT, 16.7 km away, at 5,740 ft elevation (172 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Manti, UT (used) | 5,740 ft | May 11 | Oct 6 |
| Manti Radio Kmti, UT | 5,498 ft | May 31 | Sep 21 |
| Ephraim, UT | 5,498 ft | May 28 | Sep 20 |
| Salina 24 E, UT | 7,560 ft | May 29 | Sep 26 |
Frost dates near Mayfield
- Sterling, UT 84665 · last May 11, first Oct 6
- Centerfield, UT 84622 · last May 22, first Sep 25
- Gunnison, UT 84634 · last May 22, first Sep 25
- Axtell, UT 84621 · last May 22, first Sep 25
- Manti, UT 84642 · last May 11, first Oct 6
- Fayette, UT 84630 · last May 22, first Sep 25
- Redmond, UT 84652 · last May 21, first Sep 24
- Salina, UT 84654 · last May 21, first Sep 24
Frequently asked questions
- When is the last frost in Mayfield, UT?
- For ZIP code 84643, the average last spring frost (32°F) is May 11, based on NOAA 1991-2020 climate normals for the Manti, UT weather station. There is a 1-in-10 chance of a frost after June 1.
- When is the first frost in Mayfield, UT?
- The average first fall frost (32°F) is October 6. There is a 1-in-10 chance of frost by September 24, so tender plants are at risk from that point on.
- How long is the growing season in 84643?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 146 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.