Lake Oswego, OR 97207 Frost Dates
When can you plant in Lake Oswego, OR?
Typically, the last spring freeze lands around 02/11, roughly 167 days out. The first fall frost typically arrives around 12/05, about 303 frost-free days later.
The USDA Plant Hardiness Zone Map puts Lake Oswego in Zone 9a (20 to 25°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 14 weeks of growing season left in Lake Oswego before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
02/11 is the middle of 30 years of NOAA records, not a promise. Plant by 03/05 and you're betting against frost in roughly 9 years out of 10. 12/26 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Lake Oswego compares
About 303 days separate Lake Oswego's last and first frost, putting it 3,780 of 40,283 ZIP codes nationally. Within OR, it ranks 27 of 463.
Learn more
the frost range covers how to read the range around Lake Oswego's dates instead of trusting one. local microclimates covers what one yard in Lake Oswego can differ from the 97207 normal.