Frost dates for 54529Harshaw, WI
The average last spring frost in Harshaw is May 26 and the average first fall frost is September 23, giving a typical growing season of about 120 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 26
- Average first fall frost
- Sep 23
- Growing season
- 120 days
Safer after Jun 8 (1-in-10 risk)
Possible by Sep 5 (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 23 · Jun 5 · Jun 21 | Aug 23 · Sep 9 · Sep 26 | 96 days | 100% |
| Frost / freeze (32°F) | May 9 · May 26 · Jun 8 | Sep 5 · Sep 23 · Oct 7 | 120 days | 100% |
| Hard freeze (28°F) | Apr 28 · May 13 · May 29 | Sep 17 · Oct 2 · Oct 19 | 142 days | 100% |
Planting calendar for Harshaw
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 3 |
| 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 13 |
| Summer squash | Sow outdoors | Jun 11 – Jul 26 |
| Winter squash & pumpkins | Sow outdoors | Jun 25 – Jul 26 |
| Snap beans | Sow outdoors | Jun 11 – Jul 6 |
| Sweet corn | Sow outdoors | Jun 11 – Jun 3 |
| 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 24 – Jun 3 |
| Broccoli | Transplant outdoors (fall) | Jun 23 – Jul 4 |
| Cabbage | Start seeds indoors (spring) | Mar 28 – Apr 25 |
| Cabbage | Transplant outdoors (spring) | Apr 25 – May 26 |
| Cabbage | Start seeds indoors (fall) | May 14 – Jun 13 |
| Cabbage | Transplant outdoors (fall) | Jun 13 – Jul 14 |
| Leaf lettuce | Sow outdoors (spring) | Apr 25 – Jul 11 |
| Leaf lettuce | Sow outdoors (fall) | Jun 13 – Jul 30 |
| Spinach | Sow outdoors (spring) | Apr 18 – Jun 1 |
| Spinach | Sow outdoors (fall) | Jun 30 – Aug 4 |
| Radishes | Sow outdoors (spring) | Apr 25 – Jun 15 |
| Radishes | Sow outdoors (fall) | Jun 13 – Aug 14 |
| Kale | Sow outdoors (spring) | May 12 – Jun 1 |
| Kale | Sow outdoors (fall) | Jun 6 – Jul 14 |
| Carrots | Sow outdoors (spring) | May 26 – Jul 11 |
| Carrots | Sow outdoors (fall) | May 14 – Jun 29 |
| Garlic | Plant outdoors (fall) | Sep 13 – Oct 14 |
Where these dates come from
ZIP code 54529 is matched to the NOAA station Rhinelander Oneida Ap, WI, 15.2 km away, at 1,599 ft elevation (31 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Rhinelander Oneida Ap, WI (used) | 1,599 ft | May 26 | Sep 23 |
| Willow Rsvr, WI | 1,532 ft | May 13 | Oct 3 |
| Rice Rsvr Tomahawk-2, WI | 1,460 ft | May 10 | Oct 4 |
| Rhinelander, WI | 1,572 ft | May 22 | Sep 24 |
Frost dates near Harshaw
- Mc Naughton, WI 54543 · last May 26, first Sep 23
- Hazelhurst, WI 54531 · last May 23, first Sep 27
- Lake Tomahawk, WI 54539 · last May 23, first Sep 27
- Heafford Junction, WI 54532 · last May 10, first Oct 4
- Rhinelander, WI 54501 · last May 26, first Sep 23
- Tomahawk, WI 54487 · last May 10, first Oct 4
- Minocqua, WI 54548 · last May 23, first Sep 27
- Woodruff, WI 54568 · last May 23, first Sep 27
Frequently asked questions
- When is the last frost in Harshaw, WI?
- For ZIP code 54529, the average last spring frost (32°F) is May 26, based on NOAA 1991-2020 climate normals for the Rhinelander Oneida Ap, WI weather station. There is a 1-in-10 chance of a frost after June 8.
- When is the first frost in Harshaw, WI?
- The average first fall frost (32°F) is September 23. There is a 1-in-10 chance of frost by September 5, so tender plants are at risk from that point on.
- How long is the growing season in 54529?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 120 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.