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 plane tree 2026
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Plane tree typically flowers from April to May. The tree adapts well to the urban climate and is therefore often used as a street tree in cities. It is a common source of allergens, particularly in Spain and southern France.
Current pollination
LEGEND
Due to current cause:
Currently there is a poplar cotton wool on the move, which can be found as white flakes in the air or on the ground. Poplar cotton wool is the seed hairs and seed threads of the poplar tree and is completely harmless. These flakes are not pollen and do not contain allergenic proteins, hence they are hypoallergenic. Poplar seed hairs and seed threads can even filter pollen from allergenic plants from the air. Poplar pollen is usually found in the air from February to early April and is no longer responsible for allergic reactions at this time of year. However, the poplar seed hairs and seed threads usually occur together with the birch or the grass pollen season and the symptoms are therefore often incorrectly attributed to the white flakes.
Figure: Minor aeroallergens gain importance: male, open inflorescence of oak (left), flowering catkin of walnut (center) and male, open inflorescence of plane tree (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.
Wind from Northern directions may cause constant high birch pollination and first grass pollen will occur!
Long distant transport of birch pollen still occurs. This may cause high birch pollen concentrations, although the local full flower is already fading. Many birch trees finished flowering locally. This becomes apparent due to the brown color of the catkins and masses of catkins that have fallen of the trees.
Other members of the birch and beech family flower as well:
Oak is in full flower and causes high pollination on days with fair weather. The full flower of beech is already fading. Hornbeam and hop hornbeam finished flowering. All of them are cross-reactive with birch as well and can intensify symptoms in persons with birch pollen allergy.
The flower of most ash trees has ended. However, Manna ash started flowering. This tree is insect pollinated, but relevant amounts of pollen are released into the air. Manna ash can be frequently found in Vienna as city tree.
Pollination becomes more diverse and other aeroallergens become also important:
The full flower of plane tree is fading in urban areas and high pollination is not expected anymore. It is a popular city tree and thus can cause due to its frequency rapidly high pollination that lasts about two weeks.
Walnut flowers. Walnut causes rarely a pollen allergy, but is a possible source of symtpoms.
Poplar wool can be observed already in the air locally. This is not pollen, but seeds (you find more information in „due to current cause“).
The start of the flower of early grass species, sweet vernal grass and foxtail grass, is approaching. They usually announce the grass pollen season and may release first pollen now with the period of fair weather. They are found only at natural meadows and are thus not widely distributed over the city. Relevant exposition to grass pollen may occur at such places.
Pollination profile
Birch:
state of the flower: end of main pollination period/pollination
trend: constant
time of the start of the flower: average
Ash:
state of the flower: end of the main pollination period/pollination
trend: constant
time of the start of the flower: average
Plane tree:
state of the flower: main pollination period/high pollination
trend: constant
time of the start of the flower: average
Oak:
state of the flower: main pollination period/high pollination
trend: constant
time of the start of the flower: average
Beech:
state of the flower: end of main pollination period/pollination
trend: decreasing
time of the start of the flower: average
You can find the typical pollen seasons in our pollen calendar.
Pollen spectrum:
Pollen from maple, willow, poplar, the rush family, the rose family, cypress and yew is also in the air.
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.
- The Pollenservice Vienna is official partner of the Gesundheitsdienst (MA15) of the City of Vienna.