The Ogden year in pollen

Pollen seasons in Ogden: tree pollen March to June, grass May to July, and ragweed from early August until the first frost, around October 22.

Tree pollen
Grass
Ragweed
Ragweed's bar ends at the typical first frost — around October 22.

When does ragweed season end in Ogden?

Ragweed season in Ogden typically ends with the first frost, around October 22. Some years it comes as early as October 16, some as late as October 28.

A light frost around October 22 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 Ogden pollen year

AllergenTypical season
Juniper March to May
Cottonwood and aspen March to May
Maple (boxelder) March to May
Birch and alder April to May
Pine May to June
Grass May to July

Season-by-season detail is on the Utah page.

Nearby calendars

Frost dates for Ogden come from the Ogden Hinkley Airport weather station's 30-year records. Season windows reviewed August 2026.