Bonney Lake, WA 98391 Frost Dates
Bonney Lake, WA: when does the frost end?
The last spring frost here typically falls around 04/11, about 226 days from today. Fall's first freeze usually shows up around 10/30, roughly 202 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Bonney Lake in Zone 8b (15 to 20°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 9 weeks until Bonney Lake's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
04/11 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/23 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/29 and only about 1 year in 10 sees frost after that.
Bonney Lake against the rest of the dataset
Bonney Lake's growing season runs about 202 days, ranking 17,152 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 293 of 700.
Learn more
Before leaning on 98391's figures: local microclimates explains what one yard in Bonney Lake can differ from the 98391 normal, while zone vs. frost date explains why Zone 8b and Bonney Lake's frost date answer different questions.