This is your essential guide to understanding – and surviving – grass pollen season in the UK. We’ll explore when it happens, how long it lasts, and share some tips on how you can manage your allergies.

When Is Grass Pollen Season?

In the UK, grass pollen season usually lasts from the middle of May until July. These dates can fluctuate depending on weather and has two peaks during this time period.

How Long Does the Grass Pollen Season Last?

Generally speaking, grass pollen season in the UK lasts for around two months It usually starts in the middle of May before tailing off towards the middle of July but it actually has two peaks. There’s an initial peak that usually occurs in the first two weeks of June. Then there’s often a second peak in the first two weeks of July.

This second peak is generally less severe, but it can still cause problems if you have allergies or respiratory conditions such as asthma.

Different parts of the UK will have slightly different pollen seasons. For example, all pollen seasons tend to start later and end sooner in the north, and in urban areas. Plus, inland areas will generally have higher pollen counts than coastal areas.

What Time of Day is Grass Pollen Highest?

Grass releases its pollen at around 7.30 am. On warm days, the Sun heats up the ground, causing warm air to rise. And as this warm air rises, it can take grass pollen grains with it. This process takes place over the course of the day. As a result, pollen counts can be lower in the morning and higher in the afternoon.

Pollen Levels in the Evening

Towards the evening, the air will cool, and the pollen will drift back to the ground. Because of this effect, pollen counts can also be higher in the evening, and even at night.

Evening and night-time pollen can be higher in towns and cities than in rural areas. Air cools quickly in the countryside, so most of the pollen will descend in the evening. But in towns and cities, pavements and buildings give out their own heat. This means it can take much longer for the air to cool, which means that hayfever can strike long after the Sun’s set.

Does Rain Lower Grass Pollen?

Light rain and showers can lower pollen counts. This is because rain drops can attract and trap pollen grains, removing them from the air and returning them to the ground. However, heavy rains and storms can actually increase the pollen count. The strong winds that usually accompany storms and downpours can break up pollen grains into smaller particles, which can raise the overall pollen count and make symptoms worse.

Wind can also serve to sweep up greater amounts of pollen from grass, and disperse it over a wider area. Also, the overall amount of rain the UK gets in the run-up to hayfever season can make a difference to the overall pollen count. A dry spring can reduce the amount of pollen production, whereas a wet spring can encourage pollen production.

So does rain lower grass pollen? It depends. In the early months of the year, rain can encourage grasses to produce their pollen. But during grass pollen season, a certain amount of rain can remove pollen from the air, whereas a thunderstorm can actually raise the pollen count.

How to Manage a Grass Pollen Allergy

A grass pollen allergy is the most common form of hayfever. Take a look at our full guide to the various different types of pollen that can trigger allergies in the UK.

There are a few things you can do to manage a grass pollen allergy:

  • Monitor the daily pollen count in the UK. Try and stay indoors on days with high pollen counts, and keep your windows closed so as not to allow grass pollen into your home.
  • Regularly wash your clothing and bedding. Avoid drying your laundry outside, as it could attract pollen as it descends in the air.
  • Ask your chemist about over the counter hayfever treatments.

Read our full guide to dealing with the symptoms of hayfever.

Remove The Pollen From Your Home’s Atmosphere

One of the most effective ways to manage your symptoms during grass pollen season is to purify the air in your home. Remove all the pollen from your home’s atmosphere and allow clean air to circulate instead and you’ll be able to breathe easier and sleep better on days with high pollen counts.

Our Home Air Purifier can remove up to 99% of particles from the air. They can deliver 4.8 air changes per hour in rooms of up to 17m².

Head here to learn more about how our home air purifiers can help you survive grass pollen season every year.