Iowa pollen and allergy seasons
Iowa has a spring tree season and a very heavy ragweed season across its farmland in late summer.
Twelve month pollen calendar
What is active in September
Cities in Iowa
No tracked cities yet for Iowa.
Today and worst today come from live readings where available. Typical shows the usual level for this month from the seasonal profile.
Pollen is only half of what's in the air. See today's air quality in Iowa for ozone, dust, and smoke readings by city.
The Iowa allergy season
Allergy levels in Iowa peak in September, when ragweed pollen runs highest. The season moves through tree pollen around April, grass in June, weed pollen such as ragweed in September. Levels start to climb around March. The lowest pollen levels of the year arrive in January.
Common questions
When does allergy season start in Iowa?
Pollen levels in Iowa usually begin climbing in March and reach their highest point in September.
What is the worst month for allergies in Iowa?
September is typically the worst month in Iowa, driven by ragweed pollen.
When does ragweed season end in Iowa?
Ragweed pollen in Iowa usually fades by the end of October, after the first hard frost in colder areas.
When is the best time for allergies in Iowa?
January usually brings the lowest pollen levels of the year in Iowa.