Plymouth, IL 62367 Frost Dates
Plymouth, IL: when does the frost end?
The last spring frost here typically falls around 04/13, about 228 days from today. Fall's first freeze usually shows up around 10/22, roughly 191 days after the last spring frost.
Zone 6a (-10 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 Plymouth, not a forecast for this year.
Stretching the season past the first frost
With roughly 8 weeks until Plymouth's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/13 isn't a guarantee
04/13 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/30 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.
Plymouth against the rest of the dataset
About 191 days separate Plymouth's last and first frost, putting it 20,899 of 40,283 ZIP codes nationally. Within IL, it ranks 466 of 1,548.
Learn more
Before leaning on 62367's figures: local microclimates explains what one yard in Plymouth can differ from the 62367 normal, while zone vs. frost date explains why Zone 6a and Plymouth's frost date answer different questions.