Frost dates for 97079Beaverton, OR
The average last spring frost in Beaverton is April 1 and the average first fall frost is November 6, giving a typical growing season of about 222 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 1
- Average first fall frost
- Nov 6
- Growing season
- 222 days
Safer after Apr 26 (1-in-10 risk)
Possible by Oct 19 (1-in-10 risk)
First frost typically in 6 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) | Apr 11 · Apr 28 · May 16 | Oct 4 · Oct 21 · Nov 7 | 174 days | 100% |
| Frost / freeze (32°F) | Mar 5 · Apr 1 · Apr 26 | Oct 19 · Nov 6 · Dec 1 | 222 days | 100% |
| Hard freeze (28°F) | Jan 23 · Feb 26 · Mar 26 | Nov 6 · Nov 30 · Dec 27 | 275 days | 100% |
Planting calendar for Beaverton
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 | Mar 1 – May 7 |
| Tomatoes | Transplant outdoors | Apr 17 – Jul 17 |
| Peppers | Start seeds indoors | Mar 1 – Apr 1 |
| Peppers | Transplant outdoors | May 1 – Jun 1 |
| Eggplant | Start seeds indoors | Mar 18 – Apr 16 |
| Eggplant | Transplant outdoors | May 1 – Jun 1 |
| Cucumbers | Sow outdoors | May 1 – Jul 27 |
| Summer squash | Sow outdoors | Apr 17 – Jun 1 |
| Winter squash & pumpkins | Sow outdoors | May 1 – Jun 1 |
| Snap beans | Sow outdoors | Apr 17 – Aug 19 |
| Sweet corn | Sow outdoors | Apr 17 – Jul 17 |
| Watermelon & cantaloupe | Sow outdoors | May 1 – Jun 1 |
| Okra | Sow outdoors | Apr 24 – May 17 |
| Peas | Sow outdoors (spring) | Mar 1 – Apr 16 |
| Potatoes | Plant outdoors (spring) | Mar 1 – May 1 |
| Onions | Start seeds indoors (spring) | Jan 18 – Feb 14 |
| Onions | Transplant outdoors (spring) | Mar 18 – Apr 16 |
| Broccoli | Start seeds indoors (spring) | Feb 11 – Mar 17 |
| Broccoli | Transplant outdoors (spring) | Mar 18 – Apr 16 |
| Broccoli | Start seeds indoors (fall) | Jul 7 – Jul 17 |
| Broccoli | Transplant outdoors (fall) | Aug 6 – Aug 17 |
| Cabbage | Start seeds indoors (spring) | Feb 1 – Mar 1 |
| Cabbage | Transplant outdoors (spring) | Mar 1 – Apr 1 |
| Cabbage | Start seeds indoors (fall) | Jun 27 – Jul 27 |
| Cabbage | Transplant outdoors (fall) | Jul 27 – Aug 27 |
| Leaf lettuce | Sow outdoors (spring) | Mar 1 – May 17 |
| Leaf lettuce | Sow outdoors (fall) | Jul 27 – Sep 12 |
| Spinach | Sow outdoors (spring) | Feb 22 – Apr 7 |
| Spinach | Sow outdoors (fall) | Aug 13 – Sep 17 |
| Radishes | Sow outdoors (spring) | Mar 1 – Apr 21 |
| Radishes | Sow outdoors (fall) | Jul 27 – Sep 27 |
| Kale | Sow outdoors (spring) | Mar 18 – Apr 7 |
| Kale | Sow outdoors (fall) | Jul 20 – Aug 27 |
| Carrots | Sow outdoors (spring) | Apr 1 – May 17 |
| Carrots | Sow outdoors (fall) | Jun 27 – Aug 12 |
| Garlic | Plant outdoors (fall) | Oct 27 – Nov 27 |
Where these dates come from
ZIP code 97079 is matched to the NOAA station Beaverton 2 Ssw, OR, 2.4 km away, at 270 ft elevation (76 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Beaverton 2 Ssw, OR (used) | 270 ft | Apr 1 | Nov 6 |
| Nature Park-Beaverton, OR | 185 ft | Feb 11 | Dec 5 |
| Portland Kgw-Tv, OR | 159 ft | Feb 25 | Dec 1 |
| Portland-Hillsboro Ap, OR | 204 ft | Apr 16 | Oct 23 |
Frost dates near Beaverton
- Beaverton, OR 97078 · last Apr 1, first Nov 6
- Portland, OR 97223 · last Apr 1, first Nov 6
- Lake Oswego, OR 97035 · last Apr 1, first Nov 6
- Tualatin, OR 97062 · last Apr 1, first Nov 6
- Marylhurst, OR 97036 · last Mar 18, first Nov 18
- Sherwood, OR 97140 · last Mar 16, first Nov 14
- Hillsboro, OR 97123 · last Apr 16, first Oct 23
- West Linn, OR 97068 · last Mar 18, first Nov 18
Frequently asked questions
- When is the last frost in Beaverton, OR?
- For ZIP code 97079, the average last spring frost (32°F) is April 1, based on NOAA 1991-2020 climate normals for the Beaverton 2 Ssw, OR weather station. There is a 1-in-10 chance of a frost after April 26.
- When is the first frost in Beaverton, OR?
- The average first fall frost (32°F) is November 6. There is a 1-in-10 chance of frost by October 19, so tender plants are at risk from that point on.
- How long is the growing season in 97079?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 222 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.