Frost dates for 54546Mellen, WI
The average last spring frost in Mellen is May 26 and the average first fall frost is September 27, giving a typical growing season of about 125 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 26
- Average first fall frost
- Sep 27
- Growing season
- 125 days
Safer after Jun 9 (1-in-10 risk)
Possible by Sep 12 (1-in-10 risk)
Last frost typically in 211 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 24 · Jun 5 · Jun 20 | Sep 2 · Sep 18 · Sep 30 | 103 days | 100% |
| Frost / freeze (32°F) | May 8 · May 26 · Jun 9 | Sep 12 · Sep 27 · Oct 11 | 125 days | 100% |
| Hard freeze (28°F) | Apr 27 · May 12 · May 29 | Sep 23 · Oct 6 · Oct 23 | 149 days | 100% |
Planting calendar for Mellen
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 25 – Jul 1 |
| Tomatoes | Transplant outdoors | Jun 11 – Jun 7 |
| Peppers | Start seeds indoors | Apr 25 – May 26 |
| Peppers | Transplant outdoors | Jun 25 – Jul 26 |
| Eggplant | Start seeds indoors | May 12 – Jun 10 |
| Eggplant | Transplant outdoors | Jun 25 – Jul 26 |
| Cucumbers | Sow outdoors | Jun 25 – Jun 17 |
| Summer squash | Sow outdoors | Jun 11 – Jul 26 |
| Winter squash & pumpkins | Sow outdoors | Jun 25 – Jul 26 |
| Snap beans | Sow outdoors | Jun 11 – Jul 10 |
| Sweet corn | Sow outdoors | Jun 11 – Jun 7 |
| Watermelon & cantaloupe | Sow outdoors | Jun 25 – Jul 26 |
| Okra | Sow outdoors | Jun 18 – Jul 11 |
| Peas | Sow outdoors (spring) | Apr 25 – Jun 10 |
| Potatoes | Plant outdoors (spring) | Apr 25 – Jun 25 |
| Onions | Start seeds indoors (spring) | Mar 14 – Apr 10 |
| Onions | Transplant outdoors (spring) | May 12 – Jun 10 |
| Broccoli | Start seeds indoors (spring) | Apr 7 – May 11 |
| Broccoli | Transplant outdoors (spring) | May 12 – Jun 10 |
| Broccoli | Start seeds indoors (fall) | May 28 – Jun 7 |
| Broccoli | Transplant outdoors (fall) | Jun 27 – Jul 8 |
| Cabbage | Start seeds indoors (spring) | Mar 28 – Apr 25 |
| Cabbage | Transplant outdoors (spring) | Apr 25 – May 26 |
| Cabbage | Start seeds indoors (fall) | May 18 – Jun 17 |
| Cabbage | Transplant outdoors (fall) | Jun 17 – Jul 18 |
| Leaf lettuce | Sow outdoors (spring) | Apr 25 – Jul 11 |
| Leaf lettuce | Sow outdoors (fall) | Jun 17 – Aug 3 |
| Spinach | Sow outdoors (spring) | Apr 18 – Jun 1 |
| Spinach | Sow outdoors (fall) | Jul 4 – Aug 8 |
| Radishes | Sow outdoors (spring) | Apr 25 – Jun 15 |
| Radishes | Sow outdoors (fall) | Jun 17 – Aug 18 |
| Kale | Sow outdoors (spring) | May 12 – Jun 1 |
| Kale | Sow outdoors (fall) | Jun 10 – Jul 18 |
| Carrots | Sow outdoors (spring) | May 26 – Jul 11 |
| Carrots | Sow outdoors (fall) | May 18 – Jul 3 |
| Garlic | Plant outdoors (fall) | Sep 17 – Oct 18 |
Where these dates come from
ZIP code 54546 is matched to the NOAA station Mellen 4 Ne, WI, 7.7 km away, at 1,300 ft elevation (157 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Mellen 4 Ne, WI (used) | 1,300 ft | May 26 | Sep 27 |
| Saxon 1Wsw, WI | 1,165 ft | May 23 | Oct 1 |
| Clam Lake 4W, WI | 1,498 ft | May 16 | Sep 30 |
| Ashland Kennedy Mem Ap, WI | 826 ft | May 23 | Sep 29 |
Frost dates near Mellen
- High Bridge, WI 54846 · last May 26, first Sep 27
- Marengo, WI 54855 · last May 23, first Sep 29
- Glidden, WI 54527 · last May 22, first Sep 24
- Upson, WI 54565 · last May 24, first Sep 28
- Clam Lake, WI 54517 · last May 16, first Sep 30
- Saxon, WI 54559 · last May 23, first Oct 1
- Iron Belt, WI 54536 · last May 24, first Sep 28
- Odanah, WI 54861 · last May 20, first Oct 2
Frequently asked questions
- When is the last frost in Mellen, WI?
- For ZIP code 54546, the average last spring frost (32°F) is May 26, based on NOAA 1991-2020 climate normals for the Mellen 4 Ne, WI weather station. There is a 1-in-10 chance of a frost after June 9.
- When is the first frost in Mellen, WI?
- The average first fall frost (32°F) is September 27. There is a 1-in-10 chance of frost by September 12, so tender plants are at risk from that point on.
- How long is the growing season in 54546?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 125 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.