Here is the text about pollen allergies and pollen seasons in Zurich, Switzerland (not Netherlands):
Pollen allergy sufferers experience symptoms like itchiness, sneezing, and runny noses. Pollen counts depend on weather and time of year.
Trees release pollen in Zurich from late March to early May. Birch, oak, and hazel trees are common allergy triggers.
Grasses pollinate from mid-May to early July. This is the peak pollen season in Zurich, with high counts on warm, sunny days.
Weeds release pollen from late July to early September. Ragweed is a common allergen, causing issues for many people in Zurich during this time.
When pollen counts are high, we suggest doing these things to help with allergies, especially on windy days when pollen is flying around.