Hazel already ready to flower

Attention, allergy sufferers! Pollen season has begun

The hazel pollen is already waiting in the wings.(Bild: LianeM - stock.adobe.com)

In Vienna and eastern Austria, allergy sufferers need to be prepared for the start of the hazel pollen count. In sunny locations, the first plants are already ready to flower.

The good news is that, in general, flowering in Vienna is expected to be below average. However, those affected should still take precautions and keep themselves regularly informed about the situation.

Purple alder pollen count completed
As usual, the purple alder began flowering at the end of December and has already finished flowering in Vienna. This city tree causes hardly any measurable pollen count, but can cause local symptoms, reports the Vienna Pollen Service of MedUni Vienna.

Strictly speaking, this year's pollen season began in the last few days of December with the flowering of the purple alder. This tree species is a hybrid and withstands the urban climate well. Unfortunately, however, its early flowering extends the alder pollen season.

The catkins of the gray alder (Alnus incana) and the black alder (Alnus gutinosa) are still firmly closed. In Vienna, the gray alder begins to bloom before the black alder, from the end of January at the latest, depending on the weather conditions.

Hazel blossom should start soon
The hazel pollen count has not yet begun. However, the first plants are already ready to flower in sunny locations. There are also reports from our neighboring country, Germany, that the hazel is beginning to flower. With sunshine and temperatures above five degrees Celsius, the first pollen count can already be expected in Vienna.

Keeping your eyes open is extremely sensible, as Maximilian Bastl from MedUni Vienna's Pollen Service Vienna recommends: "Recognizing flowering plants and avoiding the vicinity is a great advantage. The concentrations of pollen are many times higher in the immediate vicinity of the source."

But there are also positive things to note: After a below-average season in 2024, hazel flowering will also be below average in 2025. The number of catkins producing pollen is low for the second year in a row. The tree hazel, in particular, shows hardly any stocking in some cases.

This ensures the desired high quality of the pollen forecasts. The observation of nature and in particular the development of the flowering stages of allergenic plants at different locations is an important part of the work.

365 days a year Pollenservice Vienna 
Pollen concentrations are measured and recorded 365 days a year by the Pollenservice Vienna. The pollen forecasts and information on the website are also updated at least once a week throughout the year.

Climate change is already causing significant changes in the pollen season. For example, a study has shown a significant change in the mugwort pollen season for Austria for the first time.