Frost dates for 54022River Falls, WI
The average last spring frost in River Falls is May 11 and the average first fall frost is October 1, giving a typical growing season of about 143 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 11
- Average first fall frost
- Oct 1
- Growing season
- 143 days
Safer after May 26 (1-in-10 risk)
Possible by Sep 19 (1-in-10 risk)
Last frost typically in 191 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 6 · May 23 · Jun 6 | Sep 8 · Sep 24 · Oct 6 | 123 days | 100% |
| Frost / freeze (32°F) | Apr 26 · May 11 · May 26 | Sep 19 · Oct 1 · Oct 15 | 143 days | 100% |
| Hard freeze (28°F) | Apr 16 · May 1 · May 16 | Sep 27 · Oct 11 · Oct 26 | 162 days | 100% |
Planting calendar for River Falls
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 10 – Jun 16 |
| Tomatoes | Transplant outdoors | May 27 – Jun 11 |
| Peppers | Start seeds indoors | Apr 10 – May 11 |
| Peppers | Transplant outdoors | Jun 10 – Jul 11 |
| Eggplant | Start seeds indoors | Apr 27 – May 26 |
| Eggplant | Transplant outdoors | Jun 10 – Jul 11 |
| Cucumbers | Sow outdoors | Jun 10 – Jun 21 |
| Summer squash | Sow outdoors | May 27 – Jul 11 |
| Winter squash & pumpkins | Sow outdoors | Jun 10 – Jul 11 |
| Snap beans | Sow outdoors | May 27 – Jul 14 |
| Sweet corn | Sow outdoors | May 27 – Jun 11 |
| Watermelon & cantaloupe | Sow outdoors | Jun 10 – Jul 11 |
| Okra | Sow outdoors | Jun 3 – Jun 26 |
| Peas | Sow outdoors (spring) | Apr 10 – May 26 |
| Potatoes | Plant outdoors (spring) | Apr 10 – Jun 10 |
| Onions | Start seeds indoors (spring) | Feb 27 – Mar 26 |
| Onions | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (spring) | Mar 23 – Apr 26 |
| Broccoli | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (fall) | Jun 1 – Jun 11 |
| Broccoli | Transplant outdoors (fall) | Jul 1 – Jul 12 |
| Cabbage | Start seeds indoors (spring) | Mar 13 – Apr 10 |
| Cabbage | Transplant outdoors (spring) | Apr 10 – May 11 |
| Cabbage | Start seeds indoors (fall) | May 22 – Jun 21 |
| Cabbage | Transplant outdoors (fall) | Jun 21 – Jul 22 |
| Leaf lettuce | Sow outdoors (spring) | Apr 10 – Jun 26 |
| Leaf lettuce | Sow outdoors (fall) | Jun 21 – Aug 7 |
| Spinach | Sow outdoors (spring) | Apr 3 – May 17 |
| Spinach | Sow outdoors (fall) | Jul 8 – Aug 12 |
| Radishes | Sow outdoors (spring) | Apr 10 – May 31 |
| Radishes | Sow outdoors (fall) | Jun 21 – Aug 22 |
| Kale | Sow outdoors (spring) | Apr 27 – May 17 |
| Kale | Sow outdoors (fall) | Jun 14 – Jul 22 |
| Carrots | Sow outdoors (spring) | May 11 – Jun 26 |
| Carrots | Sow outdoors (fall) | May 22 – Jul 7 |
| Garlic | Plant outdoors (fall) | Sep 21 – Oct 22 |
Where these dates come from
ZIP code 54022 is matched to the NOAA station River Falls, WI, 1.5 km away, at 940 ft elevation (51 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| River Falls, WI (used) | 940 ft | May 11 | Oct 1 |
| Ellsworth 1E, WI | 1,030 ft | May 13 | Sep 29 |
| Hastings Dam 2, MN | 680 ft | Apr 23 | Oct 19 |
| Baldwin, WI | 1,100 ft | May 6 | Oct 2 |
Frost dates near River Falls
- Lakeland, MN 55043 · last Apr 23, first Oct 19
- Afton, MN 55001 · last May 11, first Oct 1
- Prescott, WI 54021 · last May 11, first Oct 1
- Roberts, WI 54023 · last May 11, first Oct 1
- Hudson, WI 54016 · last May 11, first Oct 1
- Ellsworth, WI 54011 · last May 13, first Sep 29
- Beldenville, WI 54003 · last May 13, first Sep 29
- East Ellsworth, WI 54010 · last May 13, first Sep 29
Frequently asked questions
- When is the last frost in River Falls, WI?
- For ZIP code 54022, the average last spring frost (32°F) is May 11, based on NOAA 1991-2020 climate normals for the River Falls, WI weather station. There is a 1-in-10 chance of a frost after May 26.
- When is the first frost in River Falls, WI?
- The average first fall frost (32°F) is October 1. There is a 1-in-10 chance of frost by September 19, so tender plants are at risk from that point on.
- How long is the growing season in 54022?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 143 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.