Portsmouth, VA 23701 Frost Dates
23701, near Portsmouth, VA: the frost window
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
Portsmouth's growing season runs out in roughly 11 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 03/23 isn't a guarantee
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 8,762 of 40,283 US ZIP codes measured here, longest to shortest. Within VA, it ranks 66 of 1,178.
Learn more
Two guides worth reading on 23701: zone vs. frost date, on why Zone 8a and Portsmouth's frost date answer different questions, and the frost range, on how to read the range around Portsmouth's dates instead of trusting one.