Last frost date in Lake Oswego, Oregon
March 18
Average last frost in spring. In an early year (1 in 10) it's over by February 19; in a late year (1 in 10) it comes after April 11.
November 18
Average first frost in fall. 1 year in 10 it comes by October 30.
Source: NOAA U.S. Climate Normals 1991–2020, station Oregon City (USC00356334), 6.1 miles from Lake Oswego, elevation 167 ft. NOAA National Centers for Environmental Information. These are long-term averages, not a forecast.
This station is also the nearest one for Gladstone, Happy Valley, Oregon City and West Linn, so their frost dates are the same as Lake Oswego's.
| Early year | Average | Late year | |
|---|---|---|---|
| Last frost in spring | Feb 19 | Mar 18 | Apr 11 |
| First frost in fall | Oct 30 | Nov 18 | Dec 12 |
Frost-free days in an average year: 244
| Chance in a year | Average last in spring | Average first in fall | |
|---|---|---|---|
| Light frost (36°F) | Every year | Apr 15 | Oct 31 |
| Frost (32°F) | Every year | Mar 18 | Nov 18 |
| Hard freeze (28°F) | 10 years in 10 | Feb 12 | Dec 8 |
Nights at 32°F or colder in an average year: 30
What to plant now in Lake Oswego
- Collards plantsAug 25 – Nov 1Now
- BeetsSept 1 – Dec 1Now
- Cabbage plantsSept 1 – Dec 1Now
- CarrotsSept 1 – Nov 1Now
- DandelionSept 1 – Nov 1Now
- Head lettuce plantsSept 1 – Nov 1Now
- Leaf lettuceSept 1 – Nov 1Now
- LeeksSept 1 – Nov 1Now
- Mustard greensSept 1 – Dec 1Now
- Onion seedSept 1 – Nov 1Now
- ParsleySept 1 – Dec 31Now
- RadishesSept 1 – Dec 1Now
- TurnipsSept 1 – Nov 15Now
- Corn saladOct 1 – Dec 1Now
- Garden peasOct 1 – Dec 1Now
- Onion plants plantsOct 1 – Dec 31Now
- SpinachOct 1 – Dec 1Now
- Upland cressOct 1 – Dec 1Now
- Chervil and chivesNov 1 – Dec 31Soon
- Onion setsNov 1 – Dec 31Soon
- Spring planting calendar for an average last frost around March 20 Lake Oswego: March 18
- Fall planting calendar for an average first frost around November 20 Lake Oswego: November 18
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), “Suburban and Farm Vegetable Gardens,” tables 4 and 5. How we match the table.
Nearby in Oregon
- Beaverton 7 mi · last frost Apr 1
- Wilsonville 8 mi · last frost Mar 18
- Portland 9 mi · last frost Feb 25
- Hillsboro 14 mi · last frost Apr 16
- Gresham 14 mi · last frost Mar 16
Updated