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: Ragweed pollen season 2026
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The flowering time of ragweed (Ambrosia sp.) is from August to September. The ragweed pollen season has started already, because relevant long distance transport of pollen was measured in the end of July.
Current pollination
LEGEND
Due to current cause:
The weed pollen season progresses: the flower of mugwort fades, ragweed (Ambrosia) is in the time of its season peak.
We provide this convenient overview graph to visualize pollination during the calendar year besides our pollen calendars.
You find more about this seasonal overview here.
Copyright: MedUni Vienna, www.pollenservice.wien
Figure: Ragweed (Ambrosia) in a field and its inflorescence in detail (left): pollen is visible as yellow powder inside the flower head.
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.
Ragweed is in full flower: right in the time of the season peak!
General situation: At present, ragweed (Ambrosia) and fungal spores are the main airborne allergens.
Ragweed (Ambrosia) is in full flower. High pollination occurred as forecasted. This is also due to wind from the Southeast, that induces additional ragweed pollen to Austria. High pollination from ragweed has to be expected on days with this wind direction. A first peak has already been measured. Another peak is expected particularly for Friday, 28th of August 2026.
Why is long distance transport of pollen relevant? Ragweed is much more abundant in the Southeast of Europe than in Austria. Thus, additional ragweed pollen has to be expected during episodes with wind from the Southeast (please consult our pollen forecast „current pollination“ above).
Important: the usual period for the season peak of the ragweed pollen season is end of August/beginning of September. It is not possible to state a specific date, but the probability for the season peak is given from now on during favorable conditions (fair weather and wind from the Southeast).
The flower of common mugwort fades. Mugwort grows on fallow lands, weed fields and along the banks of the Danube.
Note: Mugwort and ragweed are cross-reactive. This means that persons concerned may react to both pollen types.
Goldenrod started to flower. It belongs to the composite family and can cause cross-reactions (with mugwort or ragweed pollen allergies). In general, golden rod is a rare allergy trigger, because it is insect-pollinated.
Fungal spores are in their main season which lasts the whole summer. In particular, Cladosporium and Alternaria spores are in the air. Fungal spore concentrations reach high values, but they are below average for the time of the year compared to the last years. The dry conditions are the cause for this situation.
Good to know: Fungal spore concentrations increase rapidly after precipitation.
Currently, nearly no pollination from grasses is measured.
Pollen from dock and plantain is in traces in the air.
Pollination profile
Ragweed:
state of the flower: main pollination period/high pollination
trend: constant
time of the start of the flower: later than average
Mugwort:
state of the flower: main pollination period/nearly no pollination
trend: constant
time of the start of the flower: average
Fungal spores:
state of the season: main period/high spore concentrations
trend: constant
time of the start of the season: average
Grasses:
state of the flower: end of the main pollination period/hardly any pollination
trend: constant
time of the start of the flower: average
You can find the typical pollen seasons in our pollen calendar.
Pollen spectrum:
Pollen from hop, Japanese pagoda tree, the hemp family, the goosefoot family, the nettle family, cypress and yew is also in the air.
Current main allergen: Fungal spores
Exposure time in Vienna: May to October
Occurrence in Vienna: The molds in focus here thrive on vegetation. This ranges from potting soil to grain fields. Note: The concentration of fungal spores outdoor has nothing to do with the occurrence of molds indoors.
Who are “the fungal spores“?
The spores of the molds Alternaria and Cladosporium are of allergological importance, especially the former. The here discussed fungal spores are the most important ones for ambient air. There is a high diversity of molds, that are present indoors and can spread on food. Molds may cause allergies, but also toxic reactions escalating to mycosis (invasion of the inner organs).
Alternaria belongs to the blackness-fungi. It grows primarily on vegetation and causes plant diseases that can result in crop failures (fruit, cereals). Persons concerned should not mow the lawn, since it is often located on dry plants. However, Alternaria is also found in the living area.
Cladosporium belongs as well to the blackness-fungi. It prefers forests, gardens, and swamps. It is the most common fungal spore in ambient air.
Cross-reactivity: In general, there is cross-reactivity to spores of other molds (e.g. Aspergillus, Epicoccum).
Current main allergen: Mugwort
Pollination time in Vienna: July to September (some times October)
Occurrence in Vienna: Mugwort has no high habitat requirements and grows in ruderal areas as well as on poor soils or gravel grounds, roadsides, constructions sites and railway embarkments.
Who is “the mugwort“?
There are a couple of species of mugwort (among others e.g. wormwood and tarragon), but mainly one species is responsible for pollination in Vienna.
Common mugwort (Artemisia vulgaris): Mugwort was used as medicinal herb and culinary herb in former times. It can grow into up to two meters high shrub and grows also in mid-altitude areas up to 1600m above sea level.
For some time now, neophyte species of mugwort from East Asia have been increasingly establishing themselves in Central Europe, which can cause a second pollination period at the end of September/beginning of October. This is primarily due to annual mugwort (Artemisia annua) and Kamchatka mugwort (Artemisia verlotiorum). Both species are considered neophytes in Austria and benefit from climate change.
Cross-reactivity to pollen of other plants: to other genera within the same family of composite plants (Asteraceae), among others ragweed
Current main allergen: Ragweed
Pollination time in Vienna: August to October
Occurrence in Vienna: Ragweed prefers disturbed land and occurs mainly on construction sites, along railway embarkments, motorways, roadsides, on farmland and fields (maize, sunflower) on the outskirts of Vienna.
Who is “the ragweed“?
Ragweed, common hogweed, annual ragweed, low ragweed (Ambrosia artemisiifolia): This is the most common ragweed species in Vienna. It was introduced as a neophyte and is meanwhile well established especially in the East and South of Austria. This species is annual and may grow up to 1,8m. It can occur also around bird houses and gardens due to contaminated bird food.
Perennial ragweed (Ambrosia psilostachya): This species produces less seed because it spreads mainly through their roots.
Giant ragweed (Ambrosia trifida): It possesses three-feathered leaves in contrast to other species of ragweed (feathered leaves) and may grow until 4m height.
Cross-reactivity to pollen of other plants: to other genera within the same family of composite plants (Asteraceae), among others mugwort
- 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.