The Aberdeen year in pollen
Pollen seasons in Aberdeen: tree pollen February to May, grass May to August, and ragweed from early August until the first frost, around September 26.
First frost lands around September 26 in Aberdeen — about 5 days earlier than South Dakota overall — which shifts when ragweed season ends here.
When does ragweed season end in Aberdeen?
Ragweed season in Aberdeen typically ends with the first frost, around September 26. Some years it comes as early as September 21, some as late as October 1.
A light frost around September 26 knocks the season down; the hard freeze that finishes it usually follows by October 4. Based on 30 years of NOAA frost records (1991–2020).
The rest of the Aberdeen pollen year
| Allergen | Typical season |
|---|---|
| Eastern red cedar | February to April |
| Elm | February to April |
| Maple | March to April |
| Oak | April to May |
| Cottonwood | April to May |
| Grass | May to August |
Season-by-season detail is on the South Dakota page.
Nearby calendars
Frost dates for Aberdeen come from the Aberdeen weather station's 30-year records. Season windows reviewed August 2026.