CA pollen report
San Jose Pollen Report
PollyMap is actively seeking a qualified local collection partner in San Jose. This guide uses regional climate and historical allergen data while we recruit a local host.
Collection coming soon to San Jose
PollyMap is actively recruiting a verified local partner in San Jose. Be the first to know — or apply to be the partner.
Pollen patterns in San Jose
In San Jose, tree pollen — including Oak, Olive, Cypress — typically dominates from late winter through spring. Bermuda grass is the most common warm-season pollinator, and Ragweed drives the largest fall pollen load.
Top trees
- Oak
- Olive
- Cypress
- Acacia
- Sycamore
Top grasses
- Bermuda
- Rye
- Fescue
Top weeds
- Ragweed
- Sagebrush
- Pigweed
Top molds
- Cladosporium
- Alternaria
- Penicillium
San Jose 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 San Jose
Explore pollen activity in nearby cities reported by the PollyMap network.
Frequently asked questions
When is allergy season in San Jose?
In San Jose, allergy season starts with tree pollen in late winter and early spring, transitions to grass pollen in May and June, and ends with weed pollen — primarily ragweed and sagebrush — from August through October.
What pollen is highest in San Jose?
The most prevalent local pollens in San Jose include Oak, Olive, Cypress in the spring season.
What months are worst for allergies in San Jose?
Most San Jose allergy sufferers report the worst symptoms during peak tree pollen in March-May and again during ragweed season in September.
Does San Jose have mold allergies?
Yes. San Jose's climate supports Cladosporium and Alternaria spore exposure, with counts typically peaking in the warm and humid months.
Why are allergies bad in San Jose?
Local geography, climate, and seasonal plant cycles all influence allergen load in San Jose. The combination of regional vegetation and weather creates predictable spring and fall pollen peaks.
Is there a local pollen collection site in San Jose?
Not yet. PollyMap is actively seeking a qualified local allergy clinic or environmental health partner in San Jose to host weekly pollen collection.
How can my clinic become a PollyMap partner in San Jose?
Clinics in San Jose can apply to become the official PollyMap collection partner. Approved partners receive PollyKits weekly, conduct 24-48 hour collections, and mail samples back for microscope analysis.
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