Frost dates for 59259Richey, MT
The average last spring frost in Richey is May 16 and the average first fall frost is September 22, giving a typical growing season of about 129 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 16
- Average first fall frost
- Sep 22
- Growing season
- 129 days
Safer after May 31 (1-in-10 risk)
Possible by Sep 10 (1-in-10 risk)
Last frost typically in 201 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 14 · May 27 · Jun 12 | Sep 1 · Sep 14 · Sep 25 | 109 days | 100% |
| Frost / freeze (32°F) | May 2 · May 16 · May 31 | Sep 10 · Sep 22 · Oct 4 | 129 days | 100% |
| Hard freeze (28°F) | Apr 20 · May 4 · May 17 | Sep 18 · Oct 1 · Oct 15 | 150 days | 100% |
Planting calendar for Richey
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 15 – Jun 21 |
| Tomatoes | Transplant outdoors | Jun 1 – Jun 2 |
| Peppers | Start seeds indoors | Apr 15 – May 16 |
| Peppers | Transplant outdoors | Jun 15 – Jul 16 |
| Eggplant | Start seeds indoors | May 2 – May 31 |
| Eggplant | Transplant outdoors | Jun 15 – Jul 16 |
| Cucumbers | Sow outdoors | Jun 15 – Jun 12 |
| Summer squash | Sow outdoors | Jun 1 – Jul 16 |
| Winter squash & pumpkins | Sow outdoors | Jun 15 – Jul 16 |
| Snap beans | Sow outdoors | Jun 1 – Jul 5 |
| Sweet corn | Sow outdoors | Jun 1 – Jun 2 |
| Watermelon & cantaloupe | Sow outdoors | Jun 15 – Jul 16 |
| Okra | Sow outdoors | Jun 8 – Jul 1 |
| Peas | Sow outdoors (spring) | Apr 15 – May 31 |
| Potatoes | Plant outdoors (spring) | Apr 15 – Jun 15 |
| Onions | Start seeds indoors (spring) | Mar 4 – Mar 31 |
| Onions | Transplant outdoors (spring) | May 2 – May 31 |
| Broccoli | Start seeds indoors (spring) | Mar 28 – May 1 |
| Broccoli | Transplant outdoors (spring) | May 2 – May 31 |
| Broccoli | Start seeds indoors (fall) | May 23 – Jun 2 |
| Broccoli | Transplant outdoors (fall) | Jun 22 – Jul 3 |
| Cabbage | Start seeds indoors (spring) | Mar 18 – Apr 15 |
| Cabbage | Transplant outdoors (spring) | Apr 15 – May 16 |
| Cabbage | Start seeds indoors (fall) | May 13 – Jun 12 |
| Cabbage | Transplant outdoors (fall) | Jun 12 – Jul 13 |
| Leaf lettuce | Sow outdoors (spring) | Apr 15 – Jul 1 |
| Leaf lettuce | Sow outdoors (fall) | Jun 12 – Jul 29 |
| Spinach | Sow outdoors (spring) | Apr 8 – May 22 |
| Spinach | Sow outdoors (fall) | Jun 29 – Aug 3 |
| Radishes | Sow outdoors (spring) | Apr 15 – Jun 5 |
| Radishes | Sow outdoors (fall) | Jun 12 – Aug 13 |
| Kale | Sow outdoors (spring) | May 2 – May 22 |
| Kale | Sow outdoors (fall) | Jun 5 – Jul 13 |
| Carrots | Sow outdoors (spring) | May 16 – Jul 1 |
| Carrots | Sow outdoors (fall) | May 13 – Jun 28 |
| Garlic | Plant outdoors (fall) | Sep 12 – Oct 13 |
Where these dates come from
ZIP code 59259 is matched to the NOAA station Vida 6 Ne, MT, 38.8 km away, at 2,284 ft elevation (327 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Vida 6 Ne, MT (used) | 2,284 ft | May 16 | Sep 22 |
| Circle, MT | 2,480 ft | May 17 | Sep 22 |
| Savage, MT | 1,978 ft | May 12 | Sep 25 |
| Glendive, MT | 2,075 ft | May 3 | Oct 4 |
Frost dates near Richey
- Bloomfield, MT 59315 · last May 17, first Sep 22
- Lambert, MT 59243 · last May 11, first Sep 27
- Vida, MT 59274 · last May 16, first Sep 22
- Lindsay, MT 59339 · last May 26, first Sep 17
- Circle, MT 59215 · last May 17, first Sep 22
- Savage, MT 59262 · last May 12, first Sep 25
- Crane, MT 59217 · last May 12, first Sep 25
- Poplar, MT 59255 · last May 24, first Sep 14
Frequently asked questions
- When is the last frost in Richey, MT?
- For ZIP code 59259, the average last spring frost (32°F) is May 16, based on NOAA 1991-2020 climate normals for the Vida 6 Ne, MT weather station. There is a 1-in-10 chance of a frost after May 31.
- When is the first frost in Richey, MT?
- The average first fall frost (32°F) is September 22. There is a 1-in-10 chance of frost by September 10, so tender plants are at risk from that point on.
- How long is the growing season in 59259?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 129 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.