The Cedar Rapids year in pollen
Pollen seasons in Cedar Rapids: tree pollen February to May, grass May to July, and ragweed from early August until the first frost, around October 11.
Tree pollen
Grass
Ragweed
When does ragweed season end in Cedar Rapids?
Ragweed season in Cedar Rapids typically ends with the first frost, around October 11. Some years it comes as early as October 5, some as late as October 16.
A light frost around October 11 knocks the season down; the hard freeze that finishes it usually follows by October 21. Based on 30 years of NOAA frost records (1991–2020).
The rest of the Cedar Rapids 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 Cedar Rapids come from the Cedar Rapids Municipal Airport weather station's 30-year records. Season windows reviewed August 2026.