Boyertown, PA 19472 Frost Dates
Boyertown, PA: when does the frost end?
Typically, the last spring freeze lands around 04/20, roughly 235 days out. Fall's first freeze usually shows up around 10/23, roughly 186 days after the last spring frost.
Zone 7a (0 to 5°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 Boyertown, not a forecast for this year.
Stretching the season past the first frost
With roughly 8 weeks until Boyertown's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/20 isn't a guarantee
04/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/05 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/06 and only about 1 year in 10 sees frost after that.
Boyertown against the rest of the dataset
At roughly 186 frost-free days, Boyertown places 22,788 of 40,283 ZIP codes in this dataset. Within PA, it ranks 655 of 2,088.
Learn more
Before leaning on 19472's figures: local microclimates explains what one yard in Boyertown can differ from the 19472 normal, while zone vs. frost date explains why Zone 7a and Boyertown's frost date answer different questions.