The Davenport year in pollen
Pollen seasons in Davenport: tree pollen February to May, grass May to July, and ragweed from early August until the first frost, around October 18.
First frost lands around October 18 in Davenport — about 7 days later than Iowa overall — which shifts when ragweed season ends here.
When does ragweed season end in Davenport?
Ragweed season in Davenport typically ends with the first frost, around October 18. Some years it comes as early as October 13, some as late as October 22.
A light frost around October 18 knocks the season down; the hard freeze that finishes it usually follows by October 27. Based on 30 years of NOAA frost records (1991–2020).
The rest of the Davenport pollen year
| Allergen | Typical season |
|---|---|
| Oak | April to May |
| Maple | March to April |
| Elm | February to April |
| Birch | April to May |
| Ash | April to May |
| Hickory and walnut | April to May |
| Grass | May to July |
Season-by-season detail is on the Iowa page.
Nearby calendars
Frost dates for Davenport come from the Moline Quad City International Airport weather station's 30-year records. Season windows reviewed August 2026.