Frost dates for 28167Union Mills, NC
The average last spring frost in Union Mills is April 5 and the average first fall frost is October 30, giving a typical growing season of about 207 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 5
- Average first fall frost
- Oct 30
- Growing season
- 207 days
Safer after Apr 20 (1-in-10 risk)
Possible by Oct 18 (1-in-10 risk)
Last frost typically in 155 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) | Apr 5 · Apr 19 · May 4 | Oct 10 · Oct 21 · Nov 3 | 186 days | 100% |
| Frost / freeze (32°F) | Mar 20 · Apr 5 · Apr 20 | Oct 18 · Oct 30 · Nov 13 | 207 days | 100% |
| Hard freeze (28°F) | Mar 8 · Mar 25 · Apr 9 | Oct 27 · Nov 10 · Nov 27 | 228 days | 100% |
Planting calendar for Union Mills
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 | Mar 5 – May 11 |
| Tomatoes | Transplant outdoors | Apr 21 – Jul 10 |
| Peppers | Start seeds indoors | Mar 5 – Apr 5 |
| Peppers | Transplant outdoors | May 5 – Jun 5 |
| Eggplant | Start seeds indoors | Mar 22 – Apr 20 |
| Eggplant | Transplant outdoors | May 5 – Jun 5 |
| Cucumbers | Sow outdoors | May 5 – Jul 20 |
| Summer squash | Sow outdoors | Apr 21 – Jun 5 |
| Winter squash & pumpkins | Sow outdoors | May 5 – Jun 5 |
| Snap beans | Sow outdoors | Apr 21 – Aug 12 |
| Sweet corn | Sow outdoors | Apr 21 – Jul 10 |
| Watermelon & cantaloupe | Sow outdoors | May 5 – Jun 5 |
| Okra | Sow outdoors | Apr 28 – May 21 |
| Peas | Sow outdoors (spring) | Mar 5 – Apr 20 |
| Potatoes | Plant outdoors (spring) | Mar 5 – May 5 |
| Onions | Start seeds indoors (spring) | Jan 22 – Feb 18 |
| Onions | Transplant outdoors (spring) | Mar 22 – Apr 20 |
| Broccoli | Start seeds indoors (spring) | Feb 15 – Mar 21 |
| Broccoli | Transplant outdoors (spring) | Mar 22 – Apr 20 |
| Broccoli | Start seeds indoors (fall) | Jun 30 – Jul 10 |
| Broccoli | Transplant outdoors (fall) | Jul 30 – Aug 10 |
| Cabbage | Start seeds indoors (spring) | Feb 5 – Mar 5 |
| Cabbage | Transplant outdoors (spring) | Mar 5 – Apr 5 |
| Cabbage | Start seeds indoors (fall) | Jun 20 – Jul 20 |
| Cabbage | Transplant outdoors (fall) | Jul 20 – Aug 20 |
| Leaf lettuce | Sow outdoors (spring) | Mar 5 – May 21 |
| Leaf lettuce | Sow outdoors (fall) | Jul 20 – Sep 5 |
| Spinach | Sow outdoors (spring) | Feb 26 – Apr 11 |
| Spinach | Sow outdoors (fall) | Aug 6 – Sep 10 |
| Radishes | Sow outdoors (spring) | Mar 5 – Apr 25 |
| Radishes | Sow outdoors (fall) | Jul 20 – Sep 20 |
| Kale | Sow outdoors (spring) | Mar 22 – Apr 11 |
| Kale | Sow outdoors (fall) | Jul 13 – Aug 20 |
| Carrots | Sow outdoors (spring) | Apr 5 – May 21 |
| Carrots | Sow outdoors (fall) | Jun 20 – Aug 5 |
| Garlic | Plant outdoors (fall) | Oct 20 – Nov 20 |
Where these dates come from
ZIP code 28167 is matched to the NOAA station Lake Lure 2, NC, 20.7 km away, at 1,040 ft elevation (0 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Lake Lure 2, NC (used) | 1,040 ft | Apr 5 | Oct 30 |
| Forest City 8 W, NC | 849 ft | Apr 11 | Oct 27 |
| Marion, NC | 1,410 ft | Apr 5 | Nov 1 |
| Old Ft Ag 3 W, NC | 1,425 ft | Apr 21 | Oct 23 |
Frost dates near Union Mills
- Rutherfordton, NC 28139 · last Apr 11, first Oct 27
- Spindale, NC 28160 · last Apr 11, first Oct 27
- Bostic, NC 28018 · last Apr 7, first Oct 28
- Lake Lure, NC 28746 · last Apr 5, first Oct 30
- Forest City, NC 28043 · last Apr 12, first Oct 25
- Nebo, NC 28761 · last Apr 5, first Nov 1
- Mill Spring, NC 28756 · last Apr 11, first Oct 27
- Marion, NC 28752 · last Apr 5, first Nov 1
Frequently asked questions
- When is the last frost in Union Mills, NC?
- For ZIP code 28167, the average last spring frost (32°F) is April 5, based on NOAA 1991-2020 climate normals for the Lake Lure 2, NC weather station. There is a 1-in-10 chance of a frost after April 20.
- When is the first frost in Union Mills, NC?
- The average first fall frost (32°F) is October 30. There is a 1-in-10 chance of frost by October 18, so tender plants are at risk from that point on.
- How long is the growing season in 28167?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 207 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.