Langford, SD 57454 Frost Dates
Langford, SD: when does the frost end?
Typically, the last spring freeze lands around 05/06, roughly 251 days out. Fall's first freeze usually shows up around 10/04, roughly 150 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Langford in Zone 4a (-30 to -25°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
With roughly 5 weeks until Langford's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Langford's last frost
05/06 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/22 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/21 and only about 1 year in 10 sees frost after that.
Langford against the rest of the dataset
Langford's growing season runs about 150 days, ranking 35,413 of 40,283 US ZIP codes measured here, longest to shortest. Within SD, it ranks 172 of 378.
Learn more
Before leaning on 57454's figures: local microclimates explains what one yard in Langford can differ from the 57454 normal, while zone vs. frost date explains why Zone 4a and Langford's frost date answer different questions.