The Three Pollen Waves
Tree pollen comes first — starting as early as January in the South, running through May. Oak, birch, cedar, elm, and maple are the primary species.
Grass pollen overlaps tree pollen's end — beginning in May, running through July or August. Timothy, Bermuda, and Kentucky bluegrass dominate.
Weed pollen (ragweed) closes the year — August through first frost. A single ragweed plant produces up to 1 billion grains per season and its pollen travels hundreds of miles on wind.
National Month-by-Month
Regional Breakdown
SOUTHEAST · Texas, Georgia, Carolinas, Florida
Earliest and longest season in the US. Oak, cedar, and pine begin January or February. The 2026 spring arrived with unusual intensity — multiple tree species pollinating simultaneously. Some years have no truly pollen-free period.
NORTHEAST · New York, New England, Pennsylvania
Later start, intense peak. Birch, oak, and maple drive spring. NYC consistently ranks in AAFA's top allergy capitals. January and February offer the only real relief.
MIDWEST · Illinois, Ohio, Michigan, Minnesota
Heavy grass pollen from vast agricultural regions. Timothy and Kentucky bluegrass dominate. Ragweed is severe across the entire region. Climate data shows the Midwest season beginning earlier each decade.
PACIFIC NORTHWEST · Washington, Oregon
Alder dominates early spring beginning as early as January — one of the most allergenic trees in the region. Below-average weed pollen overall. Rainfall patterns heavily influence daily counts.
SOUTHWEST · Arizona, New Mexico, Southern California
Unique desert allergens: palo verde, olive, and desert broom. Southern California begins tree pollen as early as January. Desert broom weed is a significant fall allergen found nowhere else in the country.
North Texas Specifically
The Dallas–Fort Worth area — including Flower Mound, Plano, Frisco, and surrounding communities — is one of the most allergy-intensive regions in the US. Mountain cedar begins in December through February. Oak takes over March through May. Grass runs June through August. Ragweed closes September through November. North Texas has fewer than 30 truly low-pollen days per year on average. See our North Texas Allergy Guide for the full local breakdown.
Stop guessing. Start knowing.
Anthos gives you a personalized daily pollen reading for your exact location — not a regional average. Know what you're facing before you step outside.
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Anthos provides general wellness information only. Nothing in this article constitutes medical advice, diagnosis, or treatment. Always consult a licensed healthcare professional before making health decisions.