Portsmouth, VA 23321 Frost Dates
Portsmouth, VA: when does the frost end?
Typically, the last spring freeze lands around 03/23, roughly 207 days out. Fall's first freeze usually shows up around 11/16, roughly 239 days after the last spring frost.
Zone 8a (10 to 15°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 Portsmouth, not a forecast for this year.
Stretching the season past the first frost
With roughly 11 weeks until Portsmouth's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Portsmouth's last frost
03/23 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/07 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/06 and only about 1 year in 10 sees frost after that.
Portsmouth against the rest of the dataset
Portsmouth's growing season runs about 239 days, ranking 8,754 of 40,283 US ZIP codes measured here, longest to shortest. Within VA, it ranks 58 of 1,178.
Learn more
Before leaning on 23321's figures: the frost range explains how to read the range around Portsmouth's dates instead of trusting one, while local microclimates explains what one yard in Portsmouth can differ from the 23321 normal.