Frost dates for 97867North Powder, OR
The average last spring frost in North Powder is May 25 and the average first fall frost is September 15, giving a typical growing season of about 111 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 25
- Average first fall frost
- Sep 15
- Growing season
- 111 days
Safer after Jun 16 (1-in-10 risk)
Possible by Sep 2 (1-in-10 risk)
Last frost typically in 204 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) | — | — | 76 days | 100% |
| Frost / freeze (32°F) | May 9 · May 25 · Jun 16 | Sep 2 · Sep 15 · Oct 1 | 111 days | 100% |
| Hard freeze (28°F) | Apr 25 · May 8 · May 23 | Sep 12 · Sep 27 · Oct 9 | 140 days | 100% |
Planting calendar for North Powder
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 24 – Jun 30 |
| Tomatoes | Transplant outdoors | Jun 10 – May 26 |
| Peppers | Start seeds indoors | Apr 24 – May 25 |
| Peppers | Transplant outdoors | Jun 24 – Jul 25 |
| Eggplant | Start seeds indoors | May 11 – Jun 9 |
| Eggplant | Transplant outdoors | Jun 24 – Jul 25 |
| Cucumbers | Sow outdoors | Jun 24 – Jun 5 |
| Summer squash | Sow outdoors | Jun 10 – Jul 25 |
| Winter squash & pumpkins | Sow outdoors | Jun 24 – Jul 25 |
| Snap beans | Sow outdoors | Jun 10 – Jun 28 |
| Sweet corn | Sow outdoors | Jun 10 – May 26 |
| Watermelon & cantaloupe | Sow outdoors | Jun 24 – Jul 25 |
| Okra | Sow outdoors | Jun 17 – Jul 10 |
| Peas | Sow outdoors (spring) | Apr 24 – Jun 9 |
| Potatoes | Plant outdoors (spring) | Apr 24 – Jun 24 |
| Onions | Start seeds indoors (spring) | Mar 13 – Apr 9 |
| Onions | Transplant outdoors (spring) | May 11 – Jun 9 |
| Broccoli | Start seeds indoors (spring) | Apr 6 – May 10 |
| Broccoli | Transplant outdoors (spring) | May 11 – Jun 9 |
| Broccoli | Start seeds indoors (fall) | May 16 – May 26 |
| Broccoli | Transplant outdoors (fall) | Jun 15 – Jun 26 |
| Cabbage | Start seeds indoors (spring) | Mar 27 – Apr 24 |
| Cabbage | Transplant outdoors (spring) | Apr 24 – May 25 |
| Cabbage | Start seeds indoors (fall) | May 6 – Jun 5 |
| Cabbage | Transplant outdoors (fall) | Jun 5 – Jul 6 |
| Leaf lettuce | Sow outdoors (spring) | Apr 24 – Jul 10 |
| Leaf lettuce | Sow outdoors (fall) | Jun 5 – Jul 22 |
| Spinach | Sow outdoors (spring) | Apr 17 – May 31 |
| Spinach | Sow outdoors (fall) | Jun 22 – Jul 27 |
| Radishes | Sow outdoors (spring) | Apr 24 – Jun 14 |
| Radishes | Sow outdoors (fall) | Jun 5 – Aug 6 |
| Kale | Sow outdoors (spring) | May 11 – May 31 |
| Kale | Sow outdoors (fall) | May 29 – Jul 6 |
| Carrots | Sow outdoors (spring) | May 25 – Jul 10 |
| Carrots | Sow outdoors (fall) | May 6 – Jun 21 |
| Garlic | Plant outdoors (fall) | Sep 5 – Oct 6 |
Where these dates come from
ZIP code 97867 is matched to the NOAA station Baker City Muni Ap, OR, 23.2 km away, at 3,361 ft elevation (57 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Baker City Muni Ap, OR (used) | 3,361 ft | May 25 | Sep 15 |
| Union, OR | 2,777 ft | May 11 | Sep 26 |
| La Grande, OR | 2,755 ft | May 6 | Oct 1 |
| Elgin, OR | 2,697 ft | May 24 | Sep 18 |
Frost dates near North Powder
- Haines, OR 97833 · last May 25, first Sep 15
- Union, OR 97883 · last May 11, first Sep 26
- Baker City, OR 97814 · last May 25, first Sep 15
- Cove, OR 97824 · last May 11, first Sep 26
- La Grande, OR 97850 · last May 6, first Oct 1
- Sumpter, OR 97877 · last —, first —
- Imbler, OR 97841 · last May 6, first Oct 1
- Summerville, OR 97876 · last May 6, first Oct 1
Frequently asked questions
- When is the last frost in North Powder, OR?
- For ZIP code 97867, the average last spring frost (32°F) is May 25, based on NOAA 1991-2020 climate normals for the Baker City Muni Ap, OR weather station. There is a 1-in-10 chance of a frost after June 16.
- When is the first frost in North Powder, OR?
- The average first fall frost (32°F) is September 15. There is a 1-in-10 chance of frost by September 2, so tender plants are at risk from that point on.
- How long is the growing season in 97867?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 111 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.