Frost dates for 97880Ukiah, OR
The average last spring frost in Ukiah is June 5 and the average first fall frost is September 14, giving a typical growing season of about 99 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jun 5
- Average first fall frost
- Sep 14
- Growing season
- 99 days
Safer after Jun 25 (1-in-10 risk)
Possible by Aug 30 (1-in-10 risk)
Last frost typically in 216 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) | — | — | 60 days | 100% |
| Frost / freeze (32°F) | May 16 · Jun 5 · Jun 25 | Aug 30 · Sep 14 · Oct 3 | 99 days | 100% |
| Hard freeze (28°F) | Apr 28 · May 13 · Jun 5 | Sep 11 · Oct 1 · Oct 18 | 140 days | 100% |
Planting calendar for Ukiah
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 | May 5 – Jul 11 |
| Tomatoes | Transplant outdoors | Jun 21 – May 25 |
| Peppers | Start seeds indoors | May 5 – Jun 5 |
| Peppers | Transplant outdoors | Jul 5 – Aug 5 |
| Eggplant | Start seeds indoors | May 22 – Jun 20 |
| Eggplant | Transplant outdoors | Jul 5 – Aug 5 |
| Cucumbers | Sow outdoors | Jul 5 – Jun 4 |
| Summer squash | Sow outdoors | Jun 21 – Aug 5 |
| Winter squash & pumpkins | Sow outdoors | Jul 5 – Aug 5 |
| Snap beans | Sow outdoors | Jun 21 – Jun 27 |
| Sweet corn | Sow outdoors | Jun 21 – May 25 |
| Watermelon & cantaloupe | Sow outdoors | Jul 5 – Aug 5 |
| Okra | Sow outdoors | Jun 28 – Jul 21 |
| Peas | Sow outdoors (spring) | May 5 – Jun 20 |
| Potatoes | Plant outdoors (spring) | May 5 – Jul 5 |
| Onions | Start seeds indoors (spring) | Mar 24 – Apr 20 |
| Onions | Transplant outdoors (spring) | May 22 – Jun 20 |
| Broccoli | Start seeds indoors (spring) | Apr 17 – May 21 |
| Broccoli | Transplant outdoors (spring) | May 22 – Jun 20 |
| Broccoli | Start seeds indoors (fall) | May 15 – May 25 |
| Broccoli | Transplant outdoors (fall) | Jun 14 – Jun 25 |
| Cabbage | Start seeds indoors (spring) | Apr 7 – May 5 |
| Cabbage | Transplant outdoors (spring) | May 5 – Jun 5 |
| Cabbage | Start seeds indoors (fall) | May 5 – Jun 4 |
| Cabbage | Transplant outdoors (fall) | Jun 4 – Jul 5 |
| Leaf lettuce | Sow outdoors (spring) | May 5 – Jul 21 |
| Leaf lettuce | Sow outdoors (fall) | Jun 4 – Jul 21 |
| Spinach | Sow outdoors (spring) | Apr 28 – Jun 11 |
| Spinach | Sow outdoors (fall) | Jun 21 – Jul 26 |
| Radishes | Sow outdoors (spring) | May 5 – Jun 25 |
| Radishes | Sow outdoors (fall) | Jun 4 – Aug 5 |
| Kale | Sow outdoors (spring) | May 22 – Jun 11 |
| Kale | Sow outdoors (fall) | May 28 – Jul 5 |
| Carrots | Sow outdoors (spring) | Jun 5 – Jul 21 |
| Carrots | Sow outdoors (fall) | May 5 – Jun 20 |
| Garlic | Plant outdoors (fall) | Sep 4 – Oct 5 |
Where these dates come from
ZIP code 97880 is matched to the NOAA station Long Creek, OR, 44.3 km away, at 3,740 ft elevation (689 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Long Creek, OR (used) | 3,740 ft | Jun 5 | Sep 14 |
| Pilot Rock 1 Se, OR | 1,720 ft | May 7 | Oct 4 |
| Monument 2, OR | 1,995 ft | May 9 | Sep 27 |
| Meacham, OR | 3,723 ft | — | — |
Frost dates near Ukiah
- Pilot Rock, OR 97868 · last May 7, first Oct 4
- Long Creek, OR 97856 · last Jun 5, first Sep 14
- Bates, OR 97817 · last —, first —
- Monument, OR 97864 · last May 9, first Sep 27
- Heppner, OR 97836 · last Apr 26, first Oct 19
- Meacham, OR 97859 · last —, first —
- Pendleton, OR 97801 · last Apr 14, first Oct 22
- Sumpter, OR 97877 · last —, first —
Frequently asked questions
- When is the last frost in Ukiah, OR?
- For ZIP code 97880, the average last spring frost (32°F) is June 5, based on NOAA 1991-2020 climate normals for the Long Creek, OR weather station. There is a 1-in-10 chance of a frost after June 25.
- When is the first frost in Ukiah, OR?
- The average first fall frost (32°F) is September 14. There is a 1-in-10 chance of frost by August 30, so tender plants are at risk from that point on.
- How long is the growing season in 97880?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 99 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.