St. John, WA 99171 Frost Dates
When can you plant in St. John, WA?
Typically, the last spring freeze lands around 05/30, roughly 275 days out. The first fall frost typically arrives around 09/04, about 94 frost-free days later.
Zone 6b (-5 to 0°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for St. John, not a forecast for this year.
What to do before the first frost
About 1 week of growing season left in St. John 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
05/30 is the middle of 30 years of NOAA records, not a promise. Plant by 05/09 and you're betting against frost in roughly 9 years out of 10. 07/13 is the safer bet, historically only a 1-in-10 chance of frost that late.
How St. John compares
At roughly 94 frost-free days, St. John places 39,846 of 40,283 ZIP codes in this dataset. Within WA, it ranks 689 of 700.
Learn more
the frost range covers how to read the range around St. John's dates instead of trusting one. local microclimates covers what one yard in St. John can differ from the 99171 normal.