Deer Park, WA 99009 Frost Dates
When can you plant in Deer Park, WA?
Typically, the last spring freeze lands around 05/22, roughly 267 days out. The first fall frost typically arrives around 09/14, about 112 frost-free days later.
The USDA Plant Hardiness Zone Map puts Deer Park in Zone 6b (-5 to 0°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 2 weeks of growing season left in Deer Park 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
05/22 is the middle of 30 years of NOAA records, not a promise. Plant by 05/02 and you're betting against frost in roughly 9 years out of 10. 06/15 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Deer Park compares
Deer Park's growing season runs about 112 days, ranking 39,420 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 668 of 700.
Learn more
local microclimates covers what one yard in Deer Park can differ from the 99009 normal. zone vs. frost date covers why Zone 6b and Deer Park's frost date answer different questions.