Frost dates for 56547Glyndon, MN
The average last spring frost in Glyndon is May 5 and the average first fall frost is October 3, giving a typical growing season of about 150 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 5
- Average first fall frost
- Oct 3
- Growing season
- 150 days
Safer after May 20 (1-in-10 risk)
Possible by Sep 22 (1-in-10 risk)
Last frost typically in 190 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 3 · May 15 · May 29 | Sep 12 · Sep 24 · Oct 5 | 131 days | 100% |
| Frost / freeze (32°F) | Apr 23 · May 5 · May 20 | Sep 22 · Oct 3 · Oct 18 | 150 days | 100% |
| Hard freeze (28°F) | Apr 12 · Apr 28 · May 9 | Oct 1 · Oct 14 · Oct 29 | 169 days | 100% |
Planting calendar for Glyndon
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 4 – Jun 10 |
| Tomatoes | Transplant outdoors | May 21 – Jun 13 |
| Peppers | Start seeds indoors | Apr 4 – May 5 |
| Peppers | Transplant outdoors | Jun 4 – Jul 5 |
| Eggplant | Start seeds indoors | Apr 21 – May 20 |
| Eggplant | Transplant outdoors | Jun 4 – Jul 5 |
| Cucumbers | Sow outdoors | Jun 4 – Jun 23 |
| Summer squash | Sow outdoors | May 21 – Jul 5 |
| Winter squash & pumpkins | Sow outdoors | Jun 4 – Jul 5 |
| Snap beans | Sow outdoors | May 21 – Jul 16 |
| Sweet corn | Sow outdoors | May 21 – Jun 13 |
| Watermelon & cantaloupe | Sow outdoors | Jun 4 – Jul 5 |
| Okra | Sow outdoors | May 28 – Jun 20 |
| Peas | Sow outdoors (spring) | Apr 4 – May 20 |
| Potatoes | Plant outdoors (spring) | Apr 4 – Jun 4 |
| Onions | Start seeds indoors (spring) | Feb 21 – Mar 20 |
| Onions | Transplant outdoors (spring) | Apr 21 – May 20 |
| Broccoli | Start seeds indoors (spring) | Mar 17 – Apr 20 |
| Broccoli | Transplant outdoors (spring) | Apr 21 – May 20 |
| Broccoli | Start seeds indoors (fall) | Jun 3 – Jun 13 |
| Broccoli | Transplant outdoors (fall) | Jul 3 – Jul 14 |
| Cabbage | Start seeds indoors (spring) | Mar 7 – Apr 4 |
| Cabbage | Transplant outdoors (spring) | Apr 4 – May 5 |
| Cabbage | Start seeds indoors (fall) | May 24 – Jun 23 |
| Cabbage | Transplant outdoors (fall) | Jun 23 – Jul 24 |
| Leaf lettuce | Sow outdoors (spring) | Apr 4 – Jun 20 |
| Leaf lettuce | Sow outdoors (fall) | Jun 23 – Aug 9 |
| Spinach | Sow outdoors (spring) | Mar 28 – May 11 |
| Spinach | Sow outdoors (fall) | Jul 10 – Aug 14 |
| Radishes | Sow outdoors (spring) | Apr 4 – May 25 |
| Radishes | Sow outdoors (fall) | Jun 23 – Aug 24 |
| Kale | Sow outdoors (spring) | Apr 21 – May 11 |
| Kale | Sow outdoors (fall) | Jun 16 – Jul 24 |
| Carrots | Sow outdoors (spring) | May 5 – Jun 20 |
| Carrots | Sow outdoors (fall) | May 24 – Jul 9 |
| Garlic | Plant outdoors (fall) | Sep 23 – Oct 24 |
Where these dates come from
ZIP code 56547 is matched to the NOAA station Moorhead, MN, 14.5 km away, at 904 ft elevation (18 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Moorhead, MN (used) | 904 ft | May 5 | Oct 3 |
| Fargo 3S, ND | 908 ft | May 4 | Oct 2 |
| Fargo Hector Intl Ap, ND | 900 ft | May 10 | Sep 30 |
| Georgetown 1 E, MN | 885 ft | May 9 | Oct 1 |
Frost dates near Glyndon
- Dilworth, MN 56529 · last May 5, first Oct 3
- Sabin, MN 56580 · last May 5, first Oct 3
- Moorhead, MN 56560 · last May 5, first Oct 3
- Hawley, MN 56549 · last May 5, first Oct 3
- Fargo, ND 58106 · last May 5, first Oct 3
- Felton, MN 56536 · last May 9, first Oct 1
- Hitterdal, MN 56552 · last May 7, first Sep 28
- Georgetown, MN 56546 · last May 9, first Oct 1
Frequently asked questions
- When is the last frost in Glyndon, MN?
- For ZIP code 56547, the average last spring frost (32°F) is May 5, based on NOAA 1991-2020 climate normals for the Moorhead, MN weather station. There is a 1-in-10 chance of a frost after May 20.
- When is the first frost in Glyndon, MN?
- The average first fall frost (32°F) is October 3. There is a 1-in-10 chance of frost by September 22, so tender plants are at risk from that point on.
- How long is the growing season in 56547?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 150 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.