Frost dates for 55738Forbes, MN
The average last spring frost in Forbes is June 5 and the average first fall frost is September 8, giving a typical growing season of about 93 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jun 5
- Average first fall frost
- Sep 8
- Growing season
- 93 days
Safer after Jun 25 (1-in-10 risk)
Possible by Aug 23 (1-in-10 risk)
Last frost typically in 213 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) | — | — | 61 days | 100% |
| Frost / freeze (32°F) | May 22 · Jun 5 · Jun 25 | Aug 23 · Sep 8 · Sep 23 | 93 days | 100% |
| Hard freeze (28°F) | May 6 · May 23 · Jun 7 | Sep 4 · Sep 21 · Oct 5 | 120 days | 100% |
Planting calendar for Forbes
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 | May 5 – Jul 11 |
| Tomatoes | Transplant outdoors | Jun 21 – May 19 |
| Peppers | Start seeds indoors | May 5 – Jun 5 |
| Peppers | Transplant outdoors | Jul 5 – Aug 5 |
| Eggplant | Start seeds indoors | May 22 – Jun 20 |
| Eggplant | Transplant outdoors | Jul 5 – Aug 5 |
| Cucumbers | Sow outdoors | Jul 5 – May 29 |
| Summer squash | Sow outdoors | Jun 21 – Aug 5 |
| Winter squash & pumpkins | Sow outdoors | Jul 5 – Aug 5 |
| Snap beans | Sow outdoors | Jun 21 – Jun 21 |
| Sweet corn | Sow outdoors | Jun 21 – May 19 |
| Watermelon & cantaloupe | Sow outdoors | Jul 5 – Aug 5 |
| Okra | Sow outdoors | Jun 28 – Jul 21 |
| Peas | Sow outdoors (spring) | May 5 – Jun 20 |
| Potatoes | Plant outdoors (spring) | May 5 – Jul 5 |
| Onions | Start seeds indoors (spring) | Mar 24 – Apr 20 |
| Onions | Transplant outdoors (spring) | May 22 – Jun 20 |
| Broccoli | Start seeds indoors (spring) | Apr 17 – May 21 |
| Broccoli | Transplant outdoors (spring) | May 22 – Jun 20 |
| Broccoli | Start seeds indoors (fall) | May 9 – May 19 |
| Broccoli | Transplant outdoors (fall) | Jun 8 – Jun 19 |
| Cabbage | Start seeds indoors (spring) | Apr 7 – May 5 |
| Cabbage | Transplant outdoors (spring) | May 5 – Jun 5 |
| Cabbage | Start seeds indoors (fall) | Apr 29 – May 29 |
| Cabbage | Transplant outdoors (fall) | May 29 – Jun 29 |
| Leaf lettuce | Sow outdoors (spring) | May 5 – Jul 21 |
| Leaf lettuce | Sow outdoors (fall) | May 29 – Jul 15 |
| Spinach | Sow outdoors (spring) | Apr 28 – Jun 11 |
| Spinach | Sow outdoors (fall) | Jun 15 – Jul 20 |
| Radishes | Sow outdoors (spring) | May 5 – Jun 25 |
| Radishes | Sow outdoors (fall) | May 29 – Jul 30 |
| Kale | Sow outdoors (spring) | May 22 – Jun 11 |
| Kale | Sow outdoors (fall) | May 22 – Jun 29 |
| Carrots | Sow outdoors (spring) | Jun 5 – Jul 21 |
| Carrots | Sow outdoors (fall) | Apr 29 – Jun 14 |
| Garlic | Plant outdoors (fall) | Aug 29 – Sep 29 |
Where these dates come from
ZIP code 55738 is matched to the NOAA station Hibbing Chisholm Hibbing Ap, MN, 17.6 km away, at 1,352 ft elevation (40 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Hibbing Chisholm Hibbing Ap, MN (used) | 1,352 ft | Jun 5 | Sep 8 |
| Cotton, MN | 1,323 ft | May 27 | Sep 20 |
| Eveleth Wwtp, MN | 1,445 ft | May 12 | Oct 1 |
| Floodwood 3 Ne, MN | 1,260 ft | May 29 | Sep 18 |
Frost dates near Forbes
- Iron, MN 55751 · last May 12, first Oct 1
- Melrude, MN 55766 · last May 27, first Sep 20
- Meadowlands, MN 55765 · last May 29, first Sep 18
- Cotton, MN 55724 · last May 27, first Sep 20
- Eveleth, MN 55734 · last May 12, first Oct 1
- Hibbing, MN 55746 · last Jun 5, first Sep 8
- Buhl, MN 55713 · last Jun 5, first Sep 8
- Makinen, MN 55763 · last May 12, first Oct 1
Frequently asked questions
- When is the last frost in Forbes, MN?
- For ZIP code 55738, the average last spring frost (32°F) is June 5, based on NOAA 1991-2020 climate normals for the Hibbing Chisholm Hibbing Ap, MN weather station. There is a 1-in-10 chance of a frost after June 25.
- When is the first frost in Forbes, MN?
- The average first fall frost (32°F) is September 8. There is a 1-in-10 chance of frost by August 23, so tender plants are at risk from that point on.
- How long is the growing season in 55738?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 93 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.