FrostDateCheck

Leonardtown, MD 20610 Frost Dates

20610, near Leonardtown, MD: the frost window

Zone 7b

Typically, the last spring freeze lands around 03/22, roughly 206 days out. Fall's first freeze usually shows up around 11/26, roughly 248 days after the last spring frost.

Leonardtown sits in USDA Zone 7b (5 to 10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.

Stretching the season past the first frost

Leonardtown's growing season runs out in roughly 13 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.

How much risk comes with planting early here

03/22 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/06 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/05 and only about 1 year in 10 sees frost after that.

Leonardtown against the rest of the dataset

At roughly 248 frost-free days, Leonardtown places 7,695 of 40,283 ZIP codes in this dataset. Within MD, it ranks 2 of 583.

Learn more

Two guides worth reading on 20610: local microclimates, on what one yard in Leonardtown can differ from the 20610 normal, and zone vs. frost date, on why Zone 7b and Leonardtown's frost date answer different questions.