Christiana, PA 17527 Frost Dates
Christiana, PA: when does the frost end?
Typically, the last spring freeze lands around 04/16, roughly 231 days out. Fall's first freeze usually shows up around 10/27, roughly 193 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 Christiana, not a forecast for this year.
Stretching the season past the first frost
With roughly 9 weeks until Christiana's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/16 isn't a guarantee
04/16 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/03 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/30 and only about 1 year in 10 sees frost after that.
Christiana against the rest of the dataset
At roughly 193 frost-free days, Christiana places 19,992 of 40,283 ZIP codes in this dataset. Within PA, it ranks 496 of 2,088.
Learn more
Before leaning on 17527's figures: local microclimates explains what one yard in Christiana can differ from the 17527 normal, while zone vs. frost date explains why Zone 7a and Christiana's frost date answer different questions.