Rosemont, MD 21758 Frost Dates
Rosemont, MD: when does the frost end?
Typically, the last spring freeze lands around 04/26, roughly 241 days out. Fall's first freeze usually shows up around 10/18, roughly 175 days after the last spring frost.
Rosemont sits in USDA Zone 7a (0 to 5°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
With roughly 7 weeks until Rosemont's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 04/26 isn't a guarantee
04/26 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/15 and only about 1 year in 10 sees frost after that.
Rosemont against the rest of the dataset
At roughly 175 frost-free days, Rosemont places 27,232 of 40,283 ZIP codes in this dataset. Within MD, it ranks 562 of 583.
Learn more
Before leaning on 21758's figures: local microclimates explains what one yard in Rosemont can differ from the 21758 normal, while zone vs. frost date explains why Zone 7a and Rosemont's frost date answer different questions.