Frost dates for 54415Blenker, WI
The average last spring frost in Blenker is May 5 and the average first fall frost is October 5, giving a typical growing season of about 150 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 5
- Average first fall frost
- Oct 5
- Growing season
- 150 days
Safer after May 20 (1-in-10 risk)
Possible by Sep 22 (1-in-10 risk)
Last frost typically in 190 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 3 · May 15 · May 30 | Sep 12 · Sep 26 · Oct 8 | 131 days | 100% |
| Frost / freeze (32°F) | Apr 22 · May 5 · May 20 | Sep 22 · Oct 5 · Oct 19 | 150 days | 100% |
| Hard freeze (28°F) | Apr 10 · Apr 25 · May 10 | Oct 1 · Oct 16 · Nov 1 | 173 days | 100% |
Planting calendar for Blenker
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 4 – Jun 10 |
| Tomatoes | Transplant outdoors | May 21 – Jun 15 |
| Peppers | Start seeds indoors | Apr 4 – May 5 |
| Peppers | Transplant outdoors | Jun 4 – Jul 5 |
| Eggplant | Start seeds indoors | Apr 21 – May 20 |
| Eggplant | Transplant outdoors | Jun 4 – Jul 5 |
| Cucumbers | Sow outdoors | Jun 4 – Jun 25 |
| Summer squash | Sow outdoors | May 21 – Jul 5 |
| Winter squash & pumpkins | Sow outdoors | Jun 4 – Jul 5 |
| Snap beans | Sow outdoors | May 21 – Jul 18 |
| Sweet corn | Sow outdoors | May 21 – Jun 15 |
| Watermelon & cantaloupe | Sow outdoors | Jun 4 – Jul 5 |
| Okra | Sow outdoors | May 28 – Jun 20 |
| Peas | Sow outdoors (spring) | Apr 4 – May 20 |
| Potatoes | Plant outdoors (spring) | Apr 4 – Jun 4 |
| Onions | Start seeds indoors (spring) | Feb 21 – Mar 20 |
| Onions | Transplant outdoors (spring) | Apr 21 – May 20 |
| Broccoli | Start seeds indoors (spring) | Mar 17 – Apr 20 |
| Broccoli | Transplant outdoors (spring) | Apr 21 – May 20 |
| Broccoli | Start seeds indoors (fall) | Jun 5 – Jun 15 |
| Broccoli | Transplant outdoors (fall) | Jul 5 – Jul 16 |
| Cabbage | Start seeds indoors (spring) | Mar 7 – Apr 4 |
| Cabbage | Transplant outdoors (spring) | Apr 4 – May 5 |
| Cabbage | Start seeds indoors (fall) | May 26 – Jun 25 |
| Cabbage | Transplant outdoors (fall) | Jun 25 – Jul 26 |
| Leaf lettuce | Sow outdoors (spring) | Apr 4 – Jun 20 |
| Leaf lettuce | Sow outdoors (fall) | Jun 25 – Aug 11 |
| Spinach | Sow outdoors (spring) | Mar 28 – May 11 |
| Spinach | Sow outdoors (fall) | Jul 12 – Aug 16 |
| Radishes | Sow outdoors (spring) | Apr 4 – May 25 |
| Radishes | Sow outdoors (fall) | Jun 25 – Aug 26 |
| Kale | Sow outdoors (spring) | Apr 21 – May 11 |
| Kale | Sow outdoors (fall) | Jun 18 – Jul 26 |
| Carrots | Sow outdoors (spring) | May 5 – Jun 20 |
| Carrots | Sow outdoors (fall) | May 26 – Jul 11 |
| Garlic | Plant outdoors (fall) | Sep 25 – Oct 26 |
Where these dates come from
ZIP code 54415 is matched to the NOAA station Marshfield Exp Farm, WI, 17.2 km away, at 1,237 ft elevation (46 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Marshfield Exp Farm, WI (used) | 1,237 ft | May 5 | Oct 5 |
| Marshfield Muni Ap, WI | 1,255 ft | May 5 | Oct 5 |
| Wisconsin Rapids, WI | 1,033 ft | May 9 | Sep 30 |
| Stevens Pt, WI | 1,079 ft | May 4 | Oct 7 |
Frost dates near Blenker
- Milladore, WI 54454 · last May 5, first Oct 5
- Auburndale, WI 54412 · last May 5, first Oct 5
- Arpin, WI 54410 · last May 5, first Oct 5
- Junction City, WI 54443 · last May 4, first Oct 7
- Hewitt, WI 54441 · last May 5, first Oct 5
- Vesper, WI 54489 · last May 9, first Sep 30
- Rudolph, WI 54475 · last May 9, first Sep 30
- Marshfield, WI 54404 · last May 5, first Oct 5
Frequently asked questions
- When is the last frost in Blenker, WI?
- For ZIP code 54415, the average last spring frost (32°F) is May 5, based on NOAA 1991-2020 climate normals for the Marshfield Exp Farm, WI weather station. There is a 1-in-10 chance of a frost after May 20.
- When is the first frost in Blenker, WI?
- The average first fall frost (32°F) is October 5. There is a 1-in-10 chance of frost by September 22, so tender plants are at risk from that point on.
- How long is the growing season in 54415?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 150 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.