The San Antonio year in pollen
Pollen seasons in San Antonio: tree pollen December to May, grass March to October, and ragweed from early August until the first frost, around December 3.
First frost lands around December 3 in San Antonio — about 4 days later than Texas overall — which shifts when ragweed season ends here.
When does ragweed season end in San Antonio?
Ragweed season in San Antonio typically ends with the first frost, around December 3. Some years it comes as early as November 25, some as late as December 13.
A light frost around December 3 knocks the season down; the hard freeze that finishes it usually follows by December 23. Based on 30 years of NOAA frost records (1991–2020).
The rest of the San Antonio pollen year
| Allergen | Typical season |
|---|---|
| Mountain cedar (Ashe juniper) | December to February |
| Oak (live oak) | March to May |
| Elm | February to April |
| Cedar elm (fall) | August to October |
| Pecan | April to May |
| Cottonwood | March to April |
| Grass | March to October |
Season-by-season detail is on the Texas page.
Nearby calendars
Frost dates for San Antonio come from the San Antonio Stinson Airport weather station's 30-year records. Season windows reviewed August 2026.