Denver, CO Cottonwood Pollen
Cottonwood pollen in Denver usually peaks around April to May, reaching Moderate at its worst. Denver's mile-high, dry climate shapes a distinct allergy year: mountain juniper on warm late-winter days, cottonwood in spring, grass through summer, and ragweed in fall.
Cottonwoods along the South Platte and city creeks release pollen in April and May, alongside the cottony seed fluff that shares their name.
Cottonwood in Denver today
Monday, July 27, 2026
Cottonwood isn't picked up by the live pollen sensors near Denver, so there's no daily number for it. Based on the season, July is typically None for Cottonwood.
See Denver's full pollen report and 5-day forecast →Cottonwood pollen by month in Denver
How cottonwood usually runs across the year. The current month is outlined.
Managing cottonwood season in Denver
If cottonwood is your trigger, start a daily antihistamine like cetirizine (Zyrtec) or loratadine (Claritin) a week or two before the April to May peak, rather than waiting for symptoms. Keep windows closed on high-count mornings, shower and change clothes after time outside, and run the AC on recirculate in the car.
When symptoms don't ease with over-the-counter medicine, an allergist in Colorado can test whether cottonwood is really what you react to and talk through longer-term options like allergy shots.
Sources
More pollen in Denver
- Denver ragweed pollen — peaks September.
- Denver grass pollen — peaks June.
- Denver sagebrush pollen — peaks August to September.
- Denver juniper pollen — peaks March to April.
- Denver pollen calendar — every allergen, month by month.
- Denver pollen count today — live tree, grass, and weed levels with a 5-day forecast.
- Colorado pollen season — the statewide calendar and other cities.
Get Denver pollen alerts
We send a free email whenever pollen is High or Very High in Denver. No spam, no daily emails when pollen is low. Just a heads-up on the days that matter.
Sign up for free alertsSeasonal pattern based on Colorado pollen data and local sources. Today's reading updated daily. MyPollenPal