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 hornbeam 2026
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Hornbeam flowers usually from mid of March until mid of May. This plant is called Carpinus scientifically and it belongs to the birch family. The allergen is very similar to the birch allergen due to this close taxonomic relationship, which may cause a cross-allergy for those with a birch pollen allergy.
Current pollination
LEGEND
Easter weekend with birch pollen peak!
Over the Easter weekend, birch pollen has to be expected. Birches are in full flower and the weather provides good conditions for pollination. The flower of other members of the birch family (hornbeam and hop hornbeam) causes also increasing pollination.
In addition, ash flowers. More in the complete pollen forecast below.
All in all an Easter weekend that requires preparation for those with pollen allergies.
The team of the Pollenservice Vienna of Medical University of Vienna wishes a Happy Easter!
Figure: The most important aeroallergens now are ash (full flower, left), hornbeam (start of flower, center) and birch (start of flower, 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.
Onset of the full flower of birches!
Birch trees started flowering on a widespread scale, although there are individuals that do not flower yet. The full flower starts now and the season peak of the birch pollen season lies ahead. The conditions for pollination improve and reach ideal preconditions with spring-like temperatures and sunshine over the Easter weekend. High pollination of birch will occur then.
Ash is still in full flower. High pollination is possible again on days with fair weather.
Hornbeam (see video highlight) and hop-hornbeam flower. They are cross-reactive with birch, and as a result, may intensify symptoms in people with birch pollen allergies. Their pollination is increasing as well.
Pollination profile
Ash:
state of the flower: main pollination period/pollination
trend: increasing
time of the start of the flower: average
Birch:
state of the flower: main pollination period/pollination
trend: increasing
time of the start of the flower: average
You can find the typical pollen seasons in our pollen calendar.
Pollen spectrum:
Pollen from elm, maple, willow, poplar, the rose family, cypress and yew is also in the air.
Current main allergen: Ash
Pollination time in Vienna: March to May
Occurrence in Vienna: Ash is a pioneer tree and can occur at different locations. It prefers damp forests, but it is often found as well in parks.
Who is “the ash“?
Three species are of relevance in Vienna.
Common ash (Fraxinus excelsior): It grows in the lowlands but can reach also higher altitudes. The shoot and twig dieback is a serious concern. Currently we cannot observe a reduction in pollination, but this could be due to a stress reaction that causes a higher pollen production.
Manna ash (Fraxinus ornus): It originates from the Mediterranean area and became endemic as decorative plant and street tree, but also as a neophyte. A particularity is that it is insect pollinated, but still wind pollinated as well in a certain extent, which results in the release of relevant ash pollen amounts in the air.
Narrow-leafed ash (Fraxinus angustifolia): It can be found in Middle Europe on occasion in parks. It originates from southern Europe.
Cross-reactivity to pollen of other plants: olive tree
Current main allergen: Birch
Birch pollen allergy is the second most prevalent pollen allergy in Vienna!
Pollination time in Vienna: March to May
Occurrence in Vienna: Birch shows a lot of characteristics resulting in being a pioneer species (low habitat demands, frost resistant, heat resistant). It is frequently planted in parks and gardens for decorative purposes.
Who is “the birch“?Weeping, silver or white birch (Betula pendula): It is popular as decorative plant and widespread.
Downy birch (Betula pubescens): It is found in collin to subalpine regions (up to 2.000m altitude).
Dwarf birch (Betula humilis): This species occurs mostly in bog woodlands and is of low relevance in Vienna.
Alpine birch (Betula nana): This birch species is not a tree, but a (dwarf) shrub, that occurs in Middle Europe at higher altitudes or on moor soils as well as in the North of Europe and is therefore insignificant for Vienna.
Cross-reactivity to pollen of other plants: alder, hazel and hornbeam
- The Pollenservice Vienna is part of the University Department of Otolaryngology, Head and Neck Surgery at Medical University of Vienna.
- The collaboration with GeoSphere Austria involves comparing forecasts and exchanging pollen and weather data.
- We cooperate scientifically with the Sonnblick Observatory of GeoSphere Austria.