Frost dates for 59525Gildford, MT
The average last spring frost in Gildford is May 24 and the average first fall frost is September 15, giving a typical growing season of about 114 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 24
- Average first fall frost
- Sep 15
- Growing season
- 114 days
Safer after Jun 7 (1-in-10 risk)
Possible by Aug 29 (1-in-10 risk)
Last frost typically in 209 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 25 · Jun 7 · Jun 26 | Aug 15 · Sep 2 · Sep 15 | 85 days | 100% |
| Frost / freeze (32°F) | May 12 · May 24 · Jun 7 | Aug 29 · Sep 15 · Sep 28 | 114 days | 100% |
| Hard freeze (28°F) | Apr 29 · May 12 · May 27 | Sep 12 · Sep 26 · Oct 6 | 136 days | 100% |
Planting calendar for Gildford
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 23 – Jun 29 |
| Tomatoes | Transplant outdoors | Jun 9 – May 26 |
| Peppers | Start seeds indoors | Apr 23 – May 24 |
| Peppers | Transplant outdoors | Jun 23 – Jul 24 |
| Eggplant | Start seeds indoors | May 10 – Jun 8 |
| Eggplant | Transplant outdoors | Jun 23 – Jul 24 |
| Cucumbers | Sow outdoors | Jun 23 – Jun 5 |
| Summer squash | Sow outdoors | Jun 9 – Jul 24 |
| Winter squash & pumpkins | Sow outdoors | Jun 23 – Jul 24 |
| Snap beans | Sow outdoors | Jun 9 – Jun 28 |
| Sweet corn | Sow outdoors | Jun 9 – May 26 |
| Watermelon & cantaloupe | Sow outdoors | Jun 23 – Jul 24 |
| Okra | Sow outdoors | Jun 16 – Jul 9 |
| Peas | Sow outdoors (spring) | Apr 23 – Jun 8 |
| Potatoes | Plant outdoors (spring) | Apr 23 – Jun 23 |
| Onions | Start seeds indoors (spring) | Mar 12 – Apr 8 |
| Onions | Transplant outdoors (spring) | May 10 – Jun 8 |
| Broccoli | Start seeds indoors (spring) | Apr 5 – May 9 |
| Broccoli | Transplant outdoors (spring) | May 10 – Jun 8 |
| Broccoli | Start seeds indoors (fall) | May 16 – May 26 |
| Broccoli | Transplant outdoors (fall) | Jun 15 – Jun 26 |
| Cabbage | Start seeds indoors (spring) | Mar 26 – Apr 23 |
| Cabbage | Transplant outdoors (spring) | Apr 23 – May 24 |
| Cabbage | Start seeds indoors (fall) | May 6 – Jun 5 |
| Cabbage | Transplant outdoors (fall) | Jun 5 – Jul 6 |
| Leaf lettuce | Sow outdoors (spring) | Apr 23 – Jul 9 |
| Leaf lettuce | Sow outdoors (fall) | Jun 5 – Jul 22 |
| Spinach | Sow outdoors (spring) | Apr 16 – May 30 |
| Spinach | Sow outdoors (fall) | Jun 22 – Jul 27 |
| Radishes | Sow outdoors (spring) | Apr 23 – Jun 13 |
| Radishes | Sow outdoors (fall) | Jun 5 – Aug 6 |
| Kale | Sow outdoors (spring) | May 10 – May 30 |
| Kale | Sow outdoors (fall) | May 29 – Jul 6 |
| Carrots | Sow outdoors (spring) | May 24 – Jul 9 |
| Carrots | Sow outdoors (fall) | May 6 – Jun 21 |
| Garlic | Plant outdoors (fall) | Sep 5 – Oct 6 |
Where these dates come from
ZIP code 59525 is matched to the NOAA station Gildford, MT, 3.4 km away, at 2,820 ft elevation (61 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Gildford, MT (used) | 2,820 ft | May 24 | Sep 15 |
| Joplin, MT | 3,323 ft | May 21 | Sep 19 |
| Ft Assiniboine, MT | 2,675 ft | May 15 | Sep 24 |
| Rudyard 21 N, MT | 3,000 ft | May 30 | Sep 11 |
Frost dates near Gildford
- Hingham, MT 59528 · last May 24, first Sep 15
- Kremlin, MT 59532 · last May 24, first Sep 15
- Rudyard, MT 59540 · last May 21, first Sep 19
- Inverness, MT 59530 · last May 21, first Sep 19
- Joplin, MT 59531 · last May 21, first Sep 19
- Havre, MT 59501 · last May 15, first Sep 23
- Box Elder, MT 59521 · last May 17, first Sep 25
- Big Sandy, MT 59520 · last May 17, first Sep 25
Frequently asked questions
- When is the last frost in Gildford, MT?
- For ZIP code 59525, the average last spring frost (32°F) is May 24, based on NOAA 1991-2020 climate normals for the Gildford, MT weather station. There is a 1-in-10 chance of a frost after June 7.
- When is the first frost in Gildford, MT?
- The average first fall frost (32°F) is September 15. There is a 1-in-10 chance of frost by August 29, so tender plants are at risk from that point on.
- How long is the growing season in 59525?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 114 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.