FrostDateCheck

Baltimore, MD 21211 Frost Dates

21211, near Baltimore, MD: the frost window

Zone 7b

Around 04/02 is the usual last spring frost, about 217 days away. Fall's first freeze usually shows up around 11/07, roughly 220 days after the last spring frost.

The USDA Plant Hardiness Zone Map puts Baltimore in Zone 7b (5 to 10°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

Baltimore's growing season runs out in roughly 10 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 Baltimore's last frost

04/02 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/20 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/13 and only about 1 year in 10 sees frost after that.

Baltimore against the rest of the dataset

At roughly 220 frost-free days, Baltimore places 12,642 of 40,283 ZIP codes in this dataset. Within MD, it ranks 149 of 583.

Learn more

Two guides worth reading on 21211: local microclimates, on what one yard in Baltimore can differ from the 21211 normal, and zone vs. frost date, on why Zone 7b and Baltimore's frost date answer different questions.