Frost dates for 56568Nielsville, MN
The average last spring frost in Nielsville is May 2 and the average first fall frost is October 9, giving a typical growing season of about 158 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 2
- Average first fall frost
- Oct 9
- Growing season
- 158 days
Safer after May 17 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 187 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) | Apr 29 · May 11 · May 24 | Sep 15 · Sep 30 · Oct 13 | 140 days | 100% |
| Frost / freeze (32°F) | Apr 15 · May 2 · May 17 | Sep 25 · Oct 9 · Oct 25 | 158 days | 100% |
| Hard freeze (28°F) | Apr 6 · Apr 23 · May 8 | Oct 2 · Oct 20 · Nov 4 | 177 days | 100% |
Planting calendar for Nielsville
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 1 – Jun 7 |
| Tomatoes | Transplant outdoors | May 18 – Jun 19 |
| Peppers | Start seeds indoors | Apr 1 – May 2 |
| Peppers | Transplant outdoors | Jun 1 – Jul 2 |
| Eggplant | Start seeds indoors | Apr 18 – May 17 |
| Eggplant | Transplant outdoors | Jun 1 – Jul 2 |
| Cucumbers | Sow outdoors | Jun 1 – Jun 29 |
| Summer squash | Sow outdoors | May 18 – Jul 2 |
| Winter squash & pumpkins | Sow outdoors | Jun 1 – Jul 2 |
| Snap beans | Sow outdoors | May 18 – Jul 22 |
| Sweet corn | Sow outdoors | May 18 – Jun 19 |
| Watermelon & cantaloupe | Sow outdoors | Jun 1 – Jul 2 |
| Okra | Sow outdoors | May 25 – Jun 17 |
| Peas | Sow outdoors (spring) | Apr 1 – May 17 |
| Potatoes | Plant outdoors (spring) | Apr 1 – Jun 1 |
| Onions | Start seeds indoors (spring) | Feb 18 – Mar 17 |
| Onions | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (spring) | Mar 14 – Apr 17 |
| Broccoli | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (fall) | Jun 9 – Jun 19 |
| Broccoli | Transplant outdoors (fall) | Jul 9 – Jul 20 |
| Cabbage | Start seeds indoors (spring) | Mar 4 – Apr 1 |
| Cabbage | Transplant outdoors (spring) | Apr 1 – May 2 |
| Cabbage | Start seeds indoors (fall) | May 30 – Jun 29 |
| Cabbage | Transplant outdoors (fall) | Jun 29 – Jul 30 |
| Leaf lettuce | Sow outdoors (spring) | Apr 1 – Jun 17 |
| Leaf lettuce | Sow outdoors (fall) | Jun 29 – Aug 15 |
| Spinach | Sow outdoors (spring) | Mar 25 – May 8 |
| Spinach | Sow outdoors (fall) | Jul 16 – Aug 20 |
| Radishes | Sow outdoors (spring) | Apr 1 – May 22 |
| Radishes | Sow outdoors (fall) | Jun 29 – Aug 30 |
| Kale | Sow outdoors (spring) | Apr 18 – May 8 |
| Kale | Sow outdoors (fall) | Jun 22 – Jul 30 |
| Carrots | Sow outdoors (spring) | May 2 – Jun 17 |
| Carrots | Sow outdoors (fall) | May 30 – Jul 15 |
| Garlic | Plant outdoors (fall) | Sep 29 – Oct 30 |
Where these dates come from
ZIP code 56568 is matched to the NOAA station Hillsboro 3 N, ND, 25.7 km away, at 910 ft elevation (44 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Hillsboro 3 N, ND (used) | 910 ft | May 2 | Oct 9 |
| Ada, MN | 907 ft | May 11 | Sep 27 |
| Crookston Nw Exp Stn, MN | 891 ft | May 11 | Sep 27 |
| Mayville, ND | 983 ft | May 13 | Sep 27 |
Frost dates near Nielsville
- Shelly, MN 56581 · last May 2, first Oct 9
- Caledonia, ND 58219 · last May 2, first Oct 9
- Cummings, ND 58223 · last May 2, first Oct 9
- Climax, MN 56523 · last May 11, first Sep 27
- Halstad, MN 56548 · last May 11, first Sep 27
- Beltrami, MN 56517 · last May 11, first Sep 27
- Buxton, ND 58218 · last May 2, first Oct 9
- Ada, MN 56510 · last May 11, first Sep 27
Frequently asked questions
- When is the last frost in Nielsville, MN?
- For ZIP code 56568, the average last spring frost (32°F) is May 2, based on NOAA 1991-2020 climate normals for the Hillsboro 3 N, ND weather station. There is a 1-in-10 chance of a frost after May 17.
- When is the first frost in Nielsville, MN?
- The average first fall frost (32°F) is October 9. There is a 1-in-10 chance of frost by September 25, so tender plants are at risk from that point on.
- How long is the growing season in 56568?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 158 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.