Pollen calendar for Europe
In October, the allergens active across Europe are ragweed.
Pollen does not arrive all at once. Trees come first, from late winter through spring; grasses take over the summer; weeds close the year. This calendar shows when each allergen is airborne across Europe, with the current month highlighted. Exact timing shifts by a few weeks with latitude — earlier around the Mediterranean, later in Scandinavia.
When each allergen is airborne
Highlighted column is October.
| J | F | M | A | M | J | J | A | S | O | N | D | Peak | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Alder | February | ||||||||||||
| Hazel | February | ||||||||||||
| Birch | April | ||||||||||||
| Oak | late April | ||||||||||||
| Grass | June and July | ||||||||||||
| Mugwort | August | ||||||||||||
| Ragweed | late August |
Each allergen in turn
Alder — peaks February
The first pollen of the year, often mistaken for a winter cold.
Hazel — peaks February
Releases alongside alder, before most trees show any leaves.
Birch — peaks April
Short and intense. Travels hundreds of kilometres on the wind.
Oak — peaks late April
Overlaps the end of birch season across central Europe.
Grass — peaks June and July
The most common trigger in Europe, and the longest season.
Mugwort — peaks August
Late-summer weed, thrives on roadsides and waste ground.
Ragweed — peaks late August
Significant in central and eastern Europe, can run into October.
Common questions
What pollen is in the air in October?
In October, the allergens active across Europe are ragweed.
When does pollen season start?
Alder and hazel can release from January in mild winters, which makes late winter the true start of the European pollen year rather than spring.
When does pollen season end?
Grass fades through August, and weed pollen such as mugwort and ragweed runs into September or October. From November to December pollen is largely absent and indoor allergens take over.
Which pollen season is the longest?
Grass. It typically runs from May into August, six to eight weeks of it at high levels, where birch is often over in two or three weeks.
Check your own city
Is pollen high today across Europe? · All cities · Live pollen map