FrostDateCheck

Trenton, NJ 08629 Frost Dates

08629, near Trenton, NJ: the frost window

Zone 7a

Around 04/17 is the usual last spring frost, about 232 days away. Fall's first freeze usually shows up around 10/28, roughly 192 days after the last spring frost.

The USDA Plant Hardiness Zone Map puts Trenton in Zone 7a (0 to 5°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

Trenton's growing season runs out in roughly 9 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.

The actual range around Trenton's last frost

04/17 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/02 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.

Trenton against the rest of the dataset

At roughly 192 frost-free days, Trenton places 20,123 of 40,283 ZIP codes in this dataset. Within NJ, it ranks 537 of 906.

Learn more

Two guides worth reading on 08629: local microclimates, on what one yard in Trenton can differ from the 08629 normal, and zone vs. frost date, on why Zone 7a and Trenton's frost date answer different questions.