CO pollen report
Fort Collins Pollen Report
Fort Collins sits where the Cache la Poudre River leaves the Rockies and meets the plains — juniper foothills on one side, prairie grass on the other. Elm and cottonwood drive the spring, grasses carry the early summer, and ragweed and sagebrush close out the fall. Front Range winds keep pollen moving across northern Colorado.
Collection coming soon to Fort Collins
PollyMap is actively recruiting a verified local partner in Fort Collins. Be the first to know — or apply to be the partner.
While we find a local clinic
Test the air at your own home in Fort Collins
No allergy clinic is reporting from Fort Collins yet. Until one does, you can order your own PollyKit — a simple air sampler you hang outdoors or indoors. Send it back and the PollyKit Lab shows you exactly what's floating in your air.
- Pollen from local trees, grasses and weeds
- Airborne mold spores
- Dust mites and other indoor allergens
Hang it outdoors
See which pollen and mold are in your yard this season.
Or hang it indoors
Check bedrooms and living spaces for mold, dust mites and more.
What drives allergies in Fort Collins
Trees: juniper, elm, and cottonwood (March – June)
Rocky Mountain juniper and Siberian elm open the season; cottonwoods (Populus) along the Poudre peak in May.
Grasses: bluegrass and prairie grasses (May – July)
Irrigated lawns and native prairie grasses pollinate heavily in June.
Weeds: ragweed and sagebrush (August – October)
Ragweed (Ambrosia) and sagebrush (Artemisia) dominate the fall across the northern Front Range.
Mold: low, irrigation-linked
The semi-arid climate keeps mold modest, with rises in irrigated landscapes and after summer storms.
Pollen patterns in Fort Collins
In Fort Collins, tree pollen — including Juniper, Cedar, Cottonwood — typically dominates from late winter through spring. Brome grass is the most common warm-season pollinator, and Sagebrush drives the largest fall pollen load.
Top trees
- Juniper
- Cedar
- Cottonwood
- Pine
- Aspen
Top grasses
- Brome
- Bluegrass
- Fescue
Top weeds
- Sagebrush
- Ragweed
- Russian thistle
Top molds
- Cladosporium
- Alternaria
Fort Collins pollen calendar
Typical monthly intensity across the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| tree | ||||||||||||
| grass | ||||||||||||
| weed | ||||||||||||
| mold |
Historical reports
Cities near Fort Collins
Explore pollen activity in nearby cities reported by the PollyMap network.
Frequently asked questions
What is the pollen count in Fort Collins today?
PollyMap publishes real, microscope-verified pollen counts for Fort Collins — measured from physical air samples. The latest report on this page shows current tree, grass, weed, and mold levels.
Is the pollen count high in Fort Collins right now?
Fort Collins' worst stretches are April–May (elm, cottonwood, juniper), June (grasses), and September (ragweed, sagebrush). The measured reports on this page show today's actual levels.
When is allergy season in Fort Collins?
March through October: trees in spring, grasses in early summer, and ragweed and sagebrush in the fall.
Does the Front Range wind make allergies worse?
Yes — downslope winds carry juniper and grass pollen across the corridor and keep it aloft; calm days often bring relief.
Are you an allergy clinic in Fort Collins? Claim your territory on PollyMap.
PollyMap is a local authority-building tool for allergy clinics, ENT practices, and any clinic that offers allergy care. By becoming the Official PollyMap Partner for your part of Fort Collins, your clinic gets credited on real pollen reports, receives ready-to-share weekly content, and becomes the go-to local expert patients trust.
We assign each partner a designated territory within the Fort Collins metro — like a franchise territory. Fort Collins has room for multiple partners, but once your area is assigned, it's locked to your clinic.
No clinic has claimed a territory in Fort Collins yet. The best areas go to the first clinics that sign up — once one does, that part of town is off the table for everyone else.
Fort Collins, Loveland, Windsor, and Wellington each make natural PollyMap territories. The first allergy clinic in each area becomes its credited pollen expert.
- Your clinic credited on every Fort Collins pollen report
- Weekly real-sample reports and ready-to-share content under your brand
- Locked territory — competing clinics can't claim your area
- Become the go-to allergy expert in your part of Fort Collins
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