Forest Grove, OR 97077 Frost Dates
When can you plant in Forest Grove, OR?
The last spring frost here typically falls around 04/16, about 231 days from today. The first fall frost typically arrives around 10/26, about 192 frost-free days later.
Forest Grove sits in USDA Zone 9a (20 to 25°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 8 weeks of growing season left in Forest Grove before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/16 isn't a guarantee
04/16 is the middle of 30 years of NOAA records, not a promise. Plant by 03/26 and you're betting against frost in roughly 9 years out of 10. 05/05 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Forest Grove compares
About 192 days separate Forest Grove's last and first frost, putting it 20,180 of 40,283 ZIP codes nationally. Within OR, it ranks 266 of 463.
Learn more
the frost range covers how to read the range around Forest Grove's dates instead of trusting one. local microclimates covers what one yard in Forest Grove can differ from the 97077 normal.