Frost dates for 56687Wilton, MN
The average last spring frost in Wilton is May 17 and the average first fall frost is September 26, giving a typical growing season of about 131 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 17
- Average first fall frost
- Sep 26
- Growing season
- 131 days
Safer after May 30 (1-in-10 risk)
Possible by Sep 12 (1-in-10 risk)
Last frost typically in 202 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 15 · May 28 · Jun 9 | Sep 1 · Sep 17 · Sep 29 | 110 days | 100% |
| Frost / freeze (32°F) | May 3 · May 17 · May 30 | Sep 12 · Sep 26 · Oct 11 | 131 days | 100% |
| Hard freeze (28°F) | Apr 25 · May 7 · May 20 | Sep 22 · Oct 6 · Oct 23 | 151 days | 100% |
Planting calendar for Wilton
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 16 – Jun 22 |
| Tomatoes | Transplant outdoors | Jun 2 – Jun 6 |
| Peppers | Start seeds indoors | Apr 16 – May 17 |
| Peppers | Transplant outdoors | Jun 16 – Jul 17 |
| Eggplant | Start seeds indoors | May 3 – Jun 1 |
| Eggplant | Transplant outdoors | Jun 16 – Jul 17 |
| Cucumbers | Sow outdoors | Jun 16 – Jun 16 |
| Summer squash | Sow outdoors | Jun 2 – Jul 17 |
| Winter squash & pumpkins | Sow outdoors | Jun 16 – Jul 17 |
| Snap beans | Sow outdoors | Jun 2 – Jul 9 |
| Sweet corn | Sow outdoors | Jun 2 – Jun 6 |
| Watermelon & cantaloupe | Sow outdoors | Jun 16 – Jul 17 |
| Okra | Sow outdoors | Jun 9 – Jul 2 |
| Peas | Sow outdoors (spring) | Apr 16 – Jun 1 |
| Potatoes | Plant outdoors (spring) | Apr 16 – Jun 16 |
| Onions | Start seeds indoors (spring) | Mar 5 – Apr 1 |
| Onions | Transplant outdoors (spring) | May 3 – Jun 1 |
| Broccoli | Start seeds indoors (spring) | Mar 29 – May 2 |
| Broccoli | Transplant outdoors (spring) | May 3 – Jun 1 |
| Broccoli | Start seeds indoors (fall) | May 27 – Jun 6 |
| Broccoli | Transplant outdoors (fall) | Jun 26 – Jul 7 |
| Cabbage | Start seeds indoors (spring) | Mar 19 – Apr 16 |
| Cabbage | Transplant outdoors (spring) | Apr 16 – May 17 |
| Cabbage | Start seeds indoors (fall) | May 17 – Jun 16 |
| Cabbage | Transplant outdoors (fall) | Jun 16 – Jul 17 |
| Leaf lettuce | Sow outdoors (spring) | Apr 16 – Jul 2 |
| Leaf lettuce | Sow outdoors (fall) | Jun 16 – Aug 2 |
| Spinach | Sow outdoors (spring) | Apr 9 – May 23 |
| Spinach | Sow outdoors (fall) | Jul 3 – Aug 7 |
| Radishes | Sow outdoors (spring) | Apr 16 – Jun 6 |
| Radishes | Sow outdoors (fall) | Jun 16 – Aug 17 |
| Kale | Sow outdoors (spring) | May 3 – May 23 |
| Kale | Sow outdoors (fall) | Jun 9 – Jul 17 |
| Carrots | Sow outdoors (spring) | May 17 – Jul 2 |
| Carrots | Sow outdoors (fall) | May 17 – Jul 2 |
| Garlic | Plant outdoors (fall) | Sep 16 – Oct 17 |
Where these dates come from
ZIP code 56687 is matched to the NOAA station Cass Lake, MN, 31.9 km away, at 1,296 ft elevation (98 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Cass Lake, MN (used) | 1,296 ft | May 17 | Sep 26 |
| Itasca Univ Of Minn, MN | 1,490 ft | May 18 | Sep 27 |
| Blackduck, MN | 1,340 ft | May 24 | Sep 17 |
| Red Lake Indian Agcy, MN | 1,216 ft | May 12 | Oct 4 |
Frost dates near Wilton
- Bemidji, MN 56619 · last May 17, first Sep 26
- Solway, MN 56678 · last May 18, first Sep 27
- Shevlin, MN 56676 · last May 18, first Sep 27
- Puposky, MN 56667 · last May 12, first Oct 4
- Tenstrike, MN 56683 · last May 24, first Sep 17
- Bagley, MN 56621 · last May 18, first Sep 27
- Leonard, MN 56652 · last May 12, first Oct 4
- Lake George, MN 56458 · last May 18, first Sep 27
Frequently asked questions
- When is the last frost in Wilton, MN?
- For ZIP code 56687, the average last spring frost (32°F) is May 17, based on NOAA 1991-2020 climate normals for the Cass Lake, MN weather station. There is a 1-in-10 chance of a frost after May 30.
- When is the first frost in Wilton, MN?
- The average first fall frost (32°F) is September 26. 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 56687?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 131 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.