Frost dates for 56350Mc Grath, MN
The average last spring frost in Mc Grath is May 10 and the average first fall frost is October 3, giving a typical growing season of about 144 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 10
- Average first fall frost
- Oct 3
- Growing season
- 144 days
Safer after May 28 (1-in-10 risk)
Possible by Sep 19 (1-in-10 risk)
Last frost typically in 188 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 8 · May 24 · Jun 7 | Sep 7 · Sep 24 · Oct 7 | 121 days | 100% |
| Frost / freeze (32°F) | Apr 27 · May 10 · May 28 | Sep 19 · Oct 3 · Oct 17 | 144 days | 100% |
| Hard freeze (28°F) | Apr 15 · Apr 30 · May 12 | Oct 1 · Oct 16 · Oct 31 | 166 days | 100% |
Planting calendar for Mc Grath
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 9 – Jun 15 |
| Tomatoes | Transplant outdoors | May 26 – Jun 13 |
| Peppers | Start seeds indoors | Apr 9 – May 10 |
| Peppers | Transplant outdoors | Jun 9 – Jul 10 |
| Eggplant | Start seeds indoors | Apr 26 – May 25 |
| Eggplant | Transplant outdoors | Jun 9 – Jul 10 |
| Cucumbers | Sow outdoors | Jun 9 – Jun 23 |
| Summer squash | Sow outdoors | May 26 – Jul 10 |
| Winter squash & pumpkins | Sow outdoors | Jun 9 – Jul 10 |
| Snap beans | Sow outdoors | May 26 – Jul 16 |
| Sweet corn | Sow outdoors | May 26 – Jun 13 |
| Watermelon & cantaloupe | Sow outdoors | Jun 9 – Jul 10 |
| Okra | Sow outdoors | Jun 2 – Jun 25 |
| Peas | Sow outdoors (spring) | Apr 9 – May 25 |
| Potatoes | Plant outdoors (spring) | Apr 9 – Jun 9 |
| Onions | Start seeds indoors (spring) | Feb 26 – Mar 25 |
| Onions | Transplant outdoors (spring) | Apr 26 – May 25 |
| Broccoli | Start seeds indoors (spring) | Mar 22 – Apr 25 |
| Broccoli | Transplant outdoors (spring) | Apr 26 – May 25 |
| Broccoli | Start seeds indoors (fall) | Jun 3 – Jun 13 |
| Broccoli | Transplant outdoors (fall) | Jul 3 – Jul 14 |
| Cabbage | Start seeds indoors (spring) | Mar 12 – Apr 9 |
| Cabbage | Transplant outdoors (spring) | Apr 9 – May 10 |
| Cabbage | Start seeds indoors (fall) | May 24 – Jun 23 |
| Cabbage | Transplant outdoors (fall) | Jun 23 – Jul 24 |
| Leaf lettuce | Sow outdoors (spring) | Apr 9 – Jun 25 |
| Leaf lettuce | Sow outdoors (fall) | Jun 23 – Aug 9 |
| Spinach | Sow outdoors (spring) | Apr 2 – May 16 |
| Spinach | Sow outdoors (fall) | Jul 10 – Aug 14 |
| Radishes | Sow outdoors (spring) | Apr 9 – May 30 |
| Radishes | Sow outdoors (fall) | Jun 23 – Aug 24 |
| Kale | Sow outdoors (spring) | Apr 26 – May 16 |
| Kale | Sow outdoors (fall) | Jun 16 – Jul 24 |
| Carrots | Sow outdoors (spring) | May 10 – Jun 25 |
| Carrots | Sow outdoors (fall) | May 24 – Jul 9 |
| Garlic | Plant outdoors (fall) | Sep 23 – Oct 24 |
Where these dates come from
ZIP code 56350 is matched to the NOAA station Isle 12N, MN, 16.8 km away, at 1,285 ft elevation (8 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Isle 12N, MN (used) | 1,285 ft | May 10 | Oct 3 |
| Sandstone 6 W, MN | 1,130 ft | May 13 | Sep 29 |
| Mora, MN | 1,018 ft | May 9 | Sep 30 |
| Hinckley, MN | 1,035 ft | May 16 | Sep 24 |
Frost dates near Mc Grath
- Isle, MN 56342 · last May 10, first Oct 3
- Wahkon, MN 56386 · last May 10, first Oct 3
- Onamia, MN 56359 · last May 10, first Oct 3
- Finlayson, MN 55735 · last May 13, first Sep 29
- Mora, MN 55051 · last May 9, first Sep 30
- Garrison, MN 56450 · last May 10, first Oct 3
- Brook Park, MN 55007 · last May 16, first Sep 24
- Aitkin, MN 56431 · last May 16, first Sep 28
Frequently asked questions
- When is the last frost in Mc Grath, MN?
- For ZIP code 56350, the average last spring frost (32°F) is May 10, based on NOAA 1991-2020 climate normals for the Isle 12N, MN weather station. There is a 1-in-10 chance of a frost after May 28.
- When is the first frost in Mc Grath, MN?
- The average first fall frost (32°F) is October 3. 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 56350?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 144 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.