When Is Allergy Season? That Depends on Your Allergy

You often hear the phrase “allergy season,” but when is allergy season, exactly? That’s a bit of a trick question. There are allergy seasons that run throughout the year, and whether you’re affected at a given time depends on what allergens your body reacts to and when those are in the air.

How Long Do Seasonal Allergies Last?

According to the Centers for Disease Control and Prevention, more than 24 million Americans experience seasonal allergies, also referred to as seasonal allergic rhinitis or hay fever.

If you’re experiencing an allergy, your symptoms will last for as long as you’re exposed to the allergen. If you’re allergic to tree pollen, for example, you may have that familiar runny nose, watery eyes and other allergy symptoms for weeks or even months while trees are blooming and tree pollen is prolific in the air.

How long seasonal allergies last differs from year to year, and it is highly dependent on the weather. When the weather is warmer and plants bloom earlier in the spring and fall, allergy season lasts longer. Your symptoms may linger as long as the pollen counts stay high.

Wondering when allergy season might begin? Take a look at the allergens common in each month of the year:

January

With the rise of cold weather, there are fewer blooming trees and plants. You may still experience allergy symptoms, though, related to non-pollen allergens such as pet dander, dust mites and mold spores. 

February

Beginning in February, you may start experiencing allergy symptoms if you’re allergic to specific tree pollens. Alder and maple trees, for example, begin to bloom in the latter parts of the month.

March

If spring comes early and warmer weather emerges, spring allergies may begin to pop up in March. While tree pollen is most common, weeds and grasses may also begin to bloom. This is when icky yellow pollen begins to cover your car.

April

April showers may bring May flowers, but April also brings a lot of tree pollen! April is considered the peak of tree pollen season, as trees such as hickory, oak, mulberry and willow bloom.

May

In May, trees continue to bloom, and grass enters the picture, too. If you’re allergic to both, this might be the month when your allergy symptoms are worst. Take steps to prevent allergy symptoms before they begin. Your doctor can advise you about different treatments ranging from allergen avoidance to over-the-counter and prescription medications to in-office allergy shots that help you build immunity.

June

You probably start getting out the lawn mower for the first time in May or early June, and for good reason. June is considered the peak for grass pollen, including varieties such as fescue, bent, Bermuda, Timothy and Johnson grass.

July

Tree pollen starts to diminish in late June or early July, but pollen counts are still high as weed pollen begins to emerge. Allergies may stir up the most during July on hot, dry, windy days.

August

Weeds of all varieties are in full bloom, including amaranth (often called pigweed), ragweed and nettle. Ragweed is the most common source of seasonal allergies in the fall.

September

If you’re allergic to any varieties of weed pollen, your allergies are likely at their worst this month. Two factors combine to make that a reality—the peak of weed pollen and blustery weather, which can spread the pollen.

October

Weed pollen can sometimes still be a factor in October, depending on where you live and the weather, but the month is often when allergies begin to diminish.

November

As the temperatures continue to cool and plants become dormant for the cold months, seasonal allergies quiet down even further. As cool weather pushes people and pets to spend more time indoors, pet dander and other allergens found in the home can cause allergies to flare.

December

Unless you’re allergic to cedar or pine trees, you are unlikely to experience plant-associated allergies during the holidays. However, indoor allergens—pet dander, dust mites and mold spores—are always a possibility unless you continually work to eliminate them from your home.

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Dealing with the effects of allergy season?

Talk to a University of Maryland Medical System Primary Care provider.

Medically reviewed by Andrea Michelle Hebert, MD.

Posted by Eric Jackson