Mill City, OR 97360 Frost Dates
When can you plant in Mill City, OR?
Typically, the last spring freeze lands around 03/09, roughly 193 days out. The first fall frost typically arrives around 12/03, about 270 frost-free days later.
The USDA Plant Hardiness Zone Map puts Mill City in Zone 8b (15 to 20°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 Mill City before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 03/09 isn't a guarantee
03/09 is the middle of 30 years of NOAA records, not a promise. Plant by 02/02 and you're betting against frost in roughly 9 years out of 10. 04/08 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Mill City compares
At roughly 270 frost-free days, Mill City places 5,596 of 40,283 ZIP codes in this dataset. Within OR, it ranks 38 of 463.
Learn more
the frost range covers how to read the range around Mill City's dates instead of trusting one. local microclimates covers what one yard in Mill City can differ from the 97360 normal.