The Durham year in pollen
Pollen seasons in Durham: tree pollen January to May, grass April to September, and ragweed from early August until the first frost, around November 4.
Tree pollen
Grass
Ragweed
When does ragweed season end in Durham?
Ragweed season in Durham typically ends with the first frost, around November 4. Some years it comes as early as October 31, some as late as November 9.
A light frost around November 4 knocks the season down; the hard freeze that finishes it usually follows by November 16. Based on 30 years of NOAA frost records (1991–2020).
The rest of the Durham pollen year
| Allergen | Typical season |
|---|---|
| Oak | March to May |
| Pine | March to May |
| Eastern red cedar | January to March |
| Maple | February to April |
| Birch | March to April |
| Hickory | April to May |
| Grass | April to September |
Season-by-season detail is on the North Carolina page.
Nearby calendars
Frost dates for Durham come from the Raleigh Durham International Airport weather station's 30-year records. Season windows reviewed August 2026.