The Peoria year in pollen
Pollen seasons in Peoria: tree pollen February to May, grass May to July, and ragweed from early August until the first frost, around October 23.
Tree pollen
Grass
Ragweed
When does ragweed season end in Peoria?
Ragweed season in Peoria typically ends with the first frost, around October 23. Some years it comes as early as October 18, some as late as October 28.
A light frost around October 23 knocks the season down; the hard freeze that finishes it usually follows by November 2. Based on 30 years of NOAA frost records (1991–2020).
The rest of the Peoria 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 Illinois page.
Nearby calendars
Frost dates for Peoria come from the Peoria Gtr Peoria Airport weather station's 30-year records. Season windows reviewed August 2026.