Mugwort pollen set to drive hay fever symptoms across the Netherlands

Mugwort is expected to become a major source of hay fever complaints during the summer vacation period, while grass pollen continues to cause symptoms at lower levels. Ragweed is also expected to emerge later in August and add to pollen-related problems, according to information on the Dutch pollen season, weeronline reported.

Mugwort grows almost everywhere in the Netherlands, but many people do not realize it can trigger hay fever. The plant usually flowers in July and August. About 10 percent of hay fever patients reportedly experience complaints caused by mugwort pollen.

Grass is still flowering, but pollen concentrations are no longer as high as they were in May and June. This is good news for people who suffer from grass pollen allergies. However, grass can still cause complaints during the summer vacation period, although symptoms are expected to be less severe. The peak grass pollen season has passed, and dry conditions are causing grass to wither.

Some early mugwort plants have already been flowering for several weeks, but they have caused little trouble so far. Complaints are expected to increase in the coming weeks as sunny and warm summer weather continues. Mugwort appears to be unaffected by the recent dry conditions and is growing strongly. The plant is expected to remain in bloom until early August.

Hay fever symptoms caused by mugwort may temporarily ease on unsettled weather days. However, those conditions are not currently expected.

After mugwort, ragweed is expected to become the next pollen source. The plant will begin flowering in the second half of August and continue through September. Ragweed pollen is highly allergenic, meaning people who are sensitive to it can experience strong hay fever symptoms even when pollen concentrations are low.

Ragweed plants have already been found in the Netherlands, but the first pollen from common ragweed is not expected until mid-August. The plant grows especially well when days become shorter and temperatures remain high.