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Pollenservice Wien

We provide here pollen forecasts and recommendations, that are based on our scientifically evaluated data and our expertise. It is our aim to inform persons concerned by pollen allergies in Vienna in a most comprehensive, accurate way and free of charge.

Video Highlight: flower of hazel 2025

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The hazel flowers in Vienna. The pollen grains are too small for the naked eye and are only in the shape of a pollen cloud to see, as can be clearly observed here in the video (©Katharina Bastl (MedUni Vienna/Pollenservice Vienna)).

Pollen is only released when the catkins are in bloom. Each male catkin can contain millions of pollen grains (between 2 and up to 8 million depending on the reference).

Current pollination

WEDNESDAY, 12. FEBRUARY
Pollen types:Hazel, Alder

LEGEND

Hardly/no pollination
Pollination
high pollination

Due to current cause:

A comparison of the different flowering stages of hazel catkins (Corylus avellana): non-flowering catkin (left), catkin ready to flower (center) and flowering catkin (right).

The hazel is in flower in the Vienna area. However, due to the lower temperatures at the beginning of the year, there are still individuals that have not yet flowered or are only ready to flower. In the non-flowering state, the catkins' covering scales are completely closed (left). When ready to flower, the covering scales are slightly raised, revealing the pollen sacs (anthers) (center). In the flowering state, the covering scales stand out clearly and the anthers release pollen.  

 


Photo: Flowering catkins of common hazel (Corylus avellana; top left), closed catkins of black alder (Alnus glutinosa; top right), flowering catkins of Turkish hazel (Corylus colurna; bottom left) and flowering catkins of gray alder (Alnus incana, bottom right).

Mid- and long-term forecast for Vienna
This forecast gives you an overview for a longer time period so that you can improve your planning.

Still rather low pollen concentrations of hazel and alder!

The hazel pollen concentrations remained at a low level despite slightly more favorable weather conditions in recent days.
The gray alder was also able to release pollen grains, but the concentrations also remained low. The black alder, which is much more common in Vienna, is also ready to start flowering.
From the current perspective, the temperatures remain constant, dropping again over the course of the week and thus keeping the pollen levels of hazel and alder low. On days with a significant rise in temperature above 5°C, the pollen concentrations can also be higher.

Pollination profile

Hazel:
state of the flower: start of flower/pollination
trend: constant
time of the start of the flower: average

Alder:
state of the flower: start of flower/pollination
trend: constant
time of the start of the flower: average

You can find the typical pollen seasons in our pollen calendar.

Tip of the season:
If you are allergic to hazel or alder pollen, you should avoid areas where these plants are more common. Hazel likes to grow on the edges of mixed and riparian forests and is more common in the Vienna Woods and along the Danube. Alder likes to grow near bodies of water, so avoid the Old Danube, New Danube, Danube Canal, Vienna River, Lobau or Liesingbach on walks.

Pollen spectrum:
Pollen from yew, cypress, poplar  and elm is also detected at our monitoring station.

Current main allergen: Hazel

Pollination time in Vienna: January to April

Occurrence in Vienna: frequently distributed in parks, gardens or planted as ornamental plant (corkscrew hazel)

Who is “the hazel“?
There are two species of relevance in Vienna.
Turkish hazel (Corylus colurna): This species is a tree unlike the common hazel, that is a shrub. It is often planted in European cities, because it is robust and tolerates urban conditions.
Common hazel (Corylus avellana): It is a shrub and prefers forest edges and field hedges.

Cross-reactivity to pollen of other plants: alder, birch and hornbeam

The GeoSphere Austria is our partner for weather forecasts and weather data. We are grateful for the professional interchange and the cooperation.