The Grand Rapids year in pollen
Pollen seasons in Grand Rapids: tree pollen March to June, grass May to July, and ragweed from mid-August until the first frost, around October 20.
Tree pollen
Grass
Ragweed
When does ragweed season end in Grand Rapids?
Ragweed season in Grand Rapids typically ends with the first frost, around October 20. Some years it comes as early as October 13, some as late as October 26.
A light frost around October 20 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 Grand Rapids pollen year
| Allergen | Typical season |
|---|---|
| Birch | April to May |
| Oak | April to June |
| Maple | March to May |
| Alder | March to April |
| Ash | April to May |
| Pine | May to June |
| Grass | May to July |
Season-by-season detail is on the Michigan page.
Nearby calendars
Frost dates for Grand Rapids come from the Grand Rapids weather station's 30-year records. Season windows reviewed August 2026.