La Grande, OR 97850 Frost Dates
97850, near La Grande, OR: the frost window
Typically, the last spring freeze lands around 05/06, roughly 251 days out. Fall's first freeze usually shows up around 10/01, roughly 146 days after the last spring frost.
La Grande sits in USDA Zone 6b (-5 to 0°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.
Stretching the season past the first frost
La Grande's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
05/06 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/21 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/26 and only about 1 year in 10 sees frost after that.
La Grande against the rest of the dataset
La Grande's growing season runs about 146 days, ranking 36,036 of 40,283 US ZIP codes measured here, longest to shortest. Within OR, it ranks 358 of 463.
Learn more
Two guides worth reading on 97850: the frost range, on how to read the range around La Grande's dates instead of trusting one, and local microclimates, on what one yard in La Grande can differ from the 97850 normal.