Pollen Types Netherlands — Birch, Grass & more

All pollen types at a glance

Click a card for more information about each pollen type and its season.

Birch pollen

April – May. The strongest allergen in the Netherlands. Birch pollen also causes cross-reactions with apple, pear, hazelnut and cherry — the so-called oral allergy syndrome.

Now: High

Grass pollen

May – August. By far the most hay fever patients (about 90%) react to grass pollen. The peak is in June and early July. Almost all grass species produce allergenic pollen.

Now: Low

Alder & Hazel

January – March. The earliest pollen of the year. Alders and hazels bloom in winter. They often cause the first hay fever symptoms of the season, sometimes as early as January.

Now: None

Mugwort & Ragweed

July – September. Mugwort (Artemisia) blooms late in summer. Ragweed is an invasive species increasingly found in the Netherlands and is extremely allergenic — even at low concentrations.

Now: None

Grain & Rye

June – August. Rye, wheat and barley produce a lot of pollen and are strongly present in agricultural regions such as North Brabant and Limburg. People with grass pollen allergy often also react to these.

Now: None

Poplar & Willow

March – May. The white fluff of poplars is seed — not the problem. However, the invisible pollen of poplar and willow do cause symptoms. They bloom early and overlap with birch pollen.

Now: Moderate

Pollen Calendar Netherlands

Which pollen type is active in which month?

Pollen type	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep
Alder & Hazel	●	●	●
Poplar & Willow		●	●	●	●
Birch pollen			●	●	●
Grass pollen					●	●	●	●
Grain & Rye						●	●	●
Mugwort & Ragweed							●	●	●

● Low ● Moderate ● High

More about pollen and hay fever

How do pollen cause hay fever?

Pollen are microscopic grains released by flowering plants to fertilise other plants. In people with an allergy tendency, the immune system recognises pollen as a threat and produces histamine and other substances. This causes the classic symptoms: sneezing, runny nose, itchy eyes and fatigue.

Not all pollen are equally allergenic. Birch pollen is known to be particularly potent, while poplar fluff — the visible white cotton — is not an allergen at all.

Cross-reactions: from birch pollen to fruit

People allergic to birch pollen sometimes also react to raw apples, pears, peaches, kiwis or hazelnuts. This is called pollen-food allergy syndrome. The proteins in the fruit resemble those of birch pollen. Heating (cooking, baking) breaks down the proteins, so cooked fruit usually causes no symptoms.

When is pollen concentration highest?

On dry, warm and windy days
Between 10:00 and 16:00 (later in urban areas)
Immediately after a spring or summer storm
After several consecutive dry days

After a rain shower, concentrations drop quickly as pollen are washed out of the air. That is the ideal moment for hay fever sufferers to be outside.

Pollen types in the Netherlands

All pollen types at a glance

Birch pollen

Grass pollen

Alder & Hazel

Mugwort & Ragweed

Grain & Rye

Poplar & Willow

Pollen Calendar Netherlands

More about pollen and hay fever

How do pollen cause hay fever?

Cross-reactions: from birch pollen to fruit

When is pollen concentration highest?