IL
Illinois Pollen Reports
Illinois experiences a humid continental climate with hot, humid summers and cold, snowy winters.
No active PollyMap Partner in Illinois yet
We're seeking a pollen partner in Illinois.
PollyMap doesn't publish cheap forecast estimates — the kind that guess what might be in the air and are often wrong by the time you read them. Every report on PollyMap is real airborne pollen and mold, captured by a PollyKit air sampler and counted under a microscope by a trained local partner.
We're actively seeking an allergy clinic or qualified collector to become the Official PollyMap Partner for Illinois. Exclusive territory, weekly content, and AI-assisted analysis included.
Pollen patterns across Illinois
Maple, birch, oak, and ash drive the spring tree season. Grass pollen peaks in late May and June, and ragweed dominates from mid-August through the first hard frost.
Illinois pollen calendar
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| tree | ||||||||||||
| grass | ||||||||||||
| weed | ||||||||||||
| mold |
Featured cities in Illinois
Don't see your city? PollyMap partners can serve any city in Illinois — request a local report below.
Don't see your city?
We cover every city in Illinois through our partner network. Request a report for your town and we'll route it to the nearest certified allergist.
Latest reports
Frequently asked questions
When is allergy season in Illinois?
Allergy season in Illinois typically runs from late winter through fall. Tree pollen rises first, followed by grass pollen in late spring and early summer, and weed pollen (especially ragweed) in late summer and fall.
What pollen is highest in Illinois?
In Illinois, the highest-pollen species are typically Maple, Oak, Birch in spring, Bluegrass grass in early summer, and Ragweed in fall.
What months are worst for allergies in Illinois?
For most people, April and May (tree pollen) and September (ragweed) are the most difficult months in Illinois, with grass pollen creating a third peak in June.
Does Illinois have mold allergies?
Yes. The region's climate supports both outdoor and indoor mold exposure — particularly Alternaria, Cladosporium. Outdoor mold spore counts often rise after rain and in fall when leaves decay.
How can clinics become PollyMap collection partners?
Qualified allergy clinics, naturopathic offices, universities, and environmental health professionals can apply to host a PollyKit and become an official PollyMap collection partner. Applications are reviewed by the PollyMap team.
Become the lead collection partner for Illinois.
PollyMap is actively seeking allergy clinics and qualified collectors in Illinois.
Apply today