Frost dates for 58007Ayr, ND
The average last spring frost in Ayr is May 10 and the average first fall frost is September 24, giving a typical growing season of about 136 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 10
- Average first fall frost
- Sep 24
- Growing season
- 136 days
Safer after May 25 (1-in-10 risk)
Possible by Sep 13 (1-in-10 risk)
Last frost typically in 196 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 9 · May 20 · Jun 3 | Sep 2 · Sep 15 · Sep 25 | 116 days | 100% |
| Frost / freeze (32°F) | Apr 30 · May 10 · May 25 | Sep 13 · Sep 24 · Oct 5 | 136 days | 100% |
| Hard freeze (28°F) | Apr 19 · May 3 · May 15 | Sep 21 · Oct 4 · Oct 17 | 153 days | 100% |
Planting calendar for Ayr
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 4 |
| 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 14 |
| Summer squash | Sow outdoors | May 26 – Jul 10 |
| Winter squash & pumpkins | Sow outdoors | Jun 9 – Jul 10 |
| Snap beans | Sow outdoors | May 26 – Jul 7 |
| Sweet corn | Sow outdoors | May 26 – Jun 4 |
| 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) | May 25 – Jun 4 |
| Broccoli | Transplant outdoors (fall) | Jun 24 – Jul 5 |
| Cabbage | Start seeds indoors (spring) | Mar 12 – Apr 9 |
| Cabbage | Transplant outdoors (spring) | Apr 9 – May 10 |
| Cabbage | Start seeds indoors (fall) | May 15 – Jun 14 |
| Cabbage | Transplant outdoors (fall) | Jun 14 – Jul 15 |
| Leaf lettuce | Sow outdoors (spring) | Apr 9 – Jun 25 |
| Leaf lettuce | Sow outdoors (fall) | Jun 14 – Jul 31 |
| Spinach | Sow outdoors (spring) | Apr 2 – May 16 |
| Spinach | Sow outdoors (fall) | Jul 1 – Aug 5 |
| Radishes | Sow outdoors (spring) | Apr 9 – May 30 |
| Radishes | Sow outdoors (fall) | Jun 14 – Aug 15 |
| Kale | Sow outdoors (spring) | Apr 26 – May 16 |
| Kale | Sow outdoors (fall) | Jun 7 – Jul 15 |
| Carrots | Sow outdoors (spring) | May 10 – Jun 25 |
| Carrots | Sow outdoors (fall) | May 15 – Jun 30 |
| Garlic | Plant outdoors (fall) | Sep 14 – Oct 15 |
Where these dates come from
ZIP code 58007 is matched to the NOAA station Colgate, ND, 29.4 km away, at 1,180 ft elevation (9 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Colgate, ND (used) | 1,180 ft | May 10 | Sep 24 |
| Casselton Agronomy Farm, ND | 935 ft | May 9 | Oct 1 |
| Valley City 3 Nnw, ND | 1,210 ft | May 13 | Sep 26 |
| Enderlin 2W, ND | 1,164 ft | May 3 | Oct 5 |
Frost dates near Ayr
- Absaraka, ND 58002 · last May 9, first Oct 1
- Buffalo, ND 58011 · last May 9, first Oct 1
- Erie, ND 58029 · last May 10, first Sep 24
- Page, ND 58064 · last May 10, first Sep 24
- Tower City, ND 58071 · last May 13, first Sep 26
- Amenia, ND 58004 · last May 9, first Oct 1
- Arthur, ND 58006 · last May 9, first Oct 1
- Wheatland, ND 58079 · last May 9, first Oct 1
Frequently asked questions
- When is the last frost in Ayr, ND?
- For ZIP code 58007, the average last spring frost (32°F) is May 10, based on NOAA 1991-2020 climate normals for the Colgate, ND weather station. There is a 1-in-10 chance of a frost after May 25.
- When is the first frost in Ayr, ND?
- The average first fall frost (32°F) is September 24. There is a 1-in-10 chance of frost by September 13, so tender plants are at risk from that point on.
- How long is the growing season in 58007?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 136 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.