Frost dates for 54844Herbster, WI
The average last spring frost in Herbster is May 31 and the average first fall frost is October 2, giving a typical growing season of about 123 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 31
- Average first fall frost
- Oct 2
- Growing season
- 123 days
Safer after Jun 13 (1-in-10 risk)
Possible by Sep 17 (1-in-10 risk)
Last frost typically in 216 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 29 · Jun 9 · Jun 20 | Sep 5 · Sep 22 · Oct 5 | 103 days | 100% |
| Frost / freeze (32°F) | May 16 · May 31 · Jun 13 | Sep 17 · Oct 2 · Oct 14 | 123 days | 100% |
| Hard freeze (28°F) | Apr 30 · May 18 · Jun 1 | Sep 27 · Oct 13 · Oct 30 | 148 days | 100% |
Planting calendar for Herbster
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 30 – Jul 6 |
| Tomatoes | Transplant outdoors | Jun 16 – Jun 12 |
| Peppers | Start seeds indoors | Apr 30 – May 31 |
| Peppers | Transplant outdoors | Jun 30 – Jul 31 |
| Eggplant | Start seeds indoors | May 17 – Jun 15 |
| Eggplant | Transplant outdoors | Jun 30 – Jul 31 |
| Cucumbers | Sow outdoors | Jun 30 – Jun 22 |
| Summer squash | Sow outdoors | Jun 16 – Jul 31 |
| Winter squash & pumpkins | Sow outdoors | Jun 30 – Jul 31 |
| Snap beans | Sow outdoors | Jun 16 – Jul 15 |
| Sweet corn | Sow outdoors | Jun 16 – Jun 12 |
| Watermelon & cantaloupe | Sow outdoors | Jun 30 – Jul 31 |
| Okra | Sow outdoors | Jun 23 – Jul 16 |
| Peas | Sow outdoors (spring) | Apr 30 – Jun 15 |
| Potatoes | Plant outdoors (spring) | Apr 30 – Jun 30 |
| Onions | Start seeds indoors (spring) | Mar 19 – Apr 15 |
| Onions | Transplant outdoors (spring) | May 17 – Jun 15 |
| Broccoli | Start seeds indoors (spring) | Apr 12 – May 16 |
| Broccoli | Transplant outdoors (spring) | May 17 – Jun 15 |
| Broccoli | Start seeds indoors (fall) | Jun 2 – Jun 12 |
| Broccoli | Transplant outdoors (fall) | Jul 2 – Jul 13 |
| Cabbage | Start seeds indoors (spring) | Apr 2 – Apr 30 |
| Cabbage | Transplant outdoors (spring) | Apr 30 – May 31 |
| Cabbage | Start seeds indoors (fall) | May 23 – Jun 22 |
| Cabbage | Transplant outdoors (fall) | Jun 22 – Jul 23 |
| Leaf lettuce | Sow outdoors (spring) | Apr 30 – Jul 16 |
| Leaf lettuce | Sow outdoors (fall) | Jun 22 – Aug 8 |
| Spinach | Sow outdoors (spring) | Apr 23 – Jun 6 |
| Spinach | Sow outdoors (fall) | Jul 9 – Aug 13 |
| Radishes | Sow outdoors (spring) | Apr 30 – Jun 20 |
| Radishes | Sow outdoors (fall) | Jun 22 – Aug 23 |
| Kale | Sow outdoors (spring) | May 17 – Jun 6 |
| Kale | Sow outdoors (fall) | Jun 15 – Jul 23 |
| Carrots | Sow outdoors (spring) | May 31 – Jul 16 |
| Carrots | Sow outdoors (fall) | May 23 – Jul 8 |
| Garlic | Plant outdoors (fall) | Sep 22 – Oct 23 |
Where these dates come from
ZIP code 54844 is matched to the NOAA station Port Wing, WI, 12.6 km away, at 651 ft elevation (84 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Port Wing, WI (used) | 651 ft | May 31 | Oct 2 |
| Bayfield Fish Hatchery, WI | 615 ft | May 23 | Oct 2 |
| Bayfield 6 N, WI | 820 ft | May 20 | Oct 8 |
| Madeline Island, WI | 660 ft | May 20 | Oct 9 |
Frost dates near Herbster
- Cornucopia, WI 54827 · last May 20, first Oct 9
- Port Wing, WI 54865 · last May 31, first Oct 2
- Washburn, WI 54891 · last May 20, first Oct 2
- Iron River, WI 54847 · last May 24, first Sep 26
- Bayfield, WI 54814 · last May 20, first Oct 9
- Brule, WI 54820 · last May 24, first Sep 26
- Benoit, WI 54816 · last May 23, first Sep 29
- Two Harbors, MN 55616 · last May 12, first Oct 6
Frequently asked questions
- When is the last frost in Herbster, WI?
- For ZIP code 54844, the average last spring frost (32°F) is May 31, based on NOAA 1991-2020 climate normals for the Port Wing, WI weather station. There is a 1-in-10 chance of a frost after June 13.
- When is the first frost in Herbster, WI?
- 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 54844?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 123 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.