Kansas City,
13:22 PM

Everyday Health: Dr. Portnoy Gives A Year-Round Guide to Your Child’s Allergies

If your child has respiratory allergies, their symptoms may get worse at certain times of the year — during an “allergy season.” But, in fact, there isn’t any single allergy season. Depending on what your child is allergic to, there may be several different times during the year when symptoms reach their peak in response to different allergens.

Use this guide to learn about the peaks and dips of some of the most common respiratory allergens throughout the year.


In terms of allergens in cold, snowy parts of the country, “There’s not much in the air in January,” says Jay M. Portnoy, MD, professor of pediatrics and division director of allergy, asthma, and immunology at Children's Mercy. 

But in certain areas of the country, allergens persist, Dr. Portnoy says. Florida, for example, has grass pollen year-round, as well as certain tree pollen, mold, and dust mites. And in warm but drier areas like Arizona, there may be pollen from plants like Bermuda grass and olive trees during winter, he says.


In areas of the country with typical seasons, the first pollen usually occurs in early February, Portnoy says. This happens even if it’s cold and snowy because it’s triggered by how sunlight shines on trees.

“The trees pollinate before they make leaves,” Portnoy says, which makes it easier for the pollen to travel by wind. Trees that bear flowers are an exception: These trees are pollinated by insects, so they produce pollen later and less overall.

March and April

Pollen season for trees continues during these months. “Each genus of tree will pollinate for about a week or two, so it’s a progression of one species and then the next,” Portnoy says. “It’s a bunch of mini-seasons,” he says, involving juniper and elm first, then maple and ash, followed by oak and walnut trees.

Portnoy says that people who are allergic to all trees will have one long allergy season, while those with specific tree allergies might have an increase in symptoms for a week or so for each type of tree.

As the weather starts to get warmer during these months, your child will probably want to get outside and play. But if he or she has a pollen allergy, the Asthma and Allergy Foundation of America (AAFA) recommends keeping an eye on the pollen count and limiting outdoor activity when the count is high. You can check pollen counts at the National Allergy Bureau of the American Academy of Allergy Asthma & Immunology (AAAAI).

May and June

Sometime in May, the pollen season for trees will end and the grass pollen season will start. This happens when the ground is warm enough and snow has melted. Pollen season for grass usually lasts until mid-June. “When it gets hot, grass goes dormant and stops pollinating,” Portnoy says.

In addition to checking the pollen count, the AAFA recommends taking these steps to reduce exposure to pollen:

  • Keep windows closed and use air conditioning
  • Make sure your child wears sunglasses and a hat while outside
  • Have your child change clothes and shower after outdoor activities
  • Wash bedding in hot water once a week

Mold also starts to appear in May and June. “It has to get warm and humid for mold to start growing,” Portnoy says.


“The middle of summer is actually a low-pollen season,” says Portnoy says. Nevertheless, there are potential allergens to look out for. Some grass may still be pollinating depending on conditions, and certain weeds will start to pollinate during this time.

Mold tends to reach its peak in July in warmer states, according to the AAAAI. But in colder states it may drop during this time, Portnoy says.

To prevent mold from becoming a problem, the American College of Allergy Asthma & Immunology (ACAAI) says to quickly fix any leaks, use dehumidifiers to reduce moisture in your home, and clean garbage cans regularly.

August and September

The fall weed season usually begins around the 15th of August, Portnoy says. Ragweed is the most common fall allergen in many parts of the country, but other weeds also pollinate during this time.

According to Portnoy, pollen levels for weeds tend to peak around September 10th. “So kids going back to school can have a lot of nasal allergy symptoms,” he says, such as sneezing, runny nose, and watery eyes.

The U.S. Environmental Protection Agency notes that the ragweed pollen season has gotten longer in many areas — by as much as 25 days — over the last 20 years. It attributes this effect in part to climate change.

During ragweed season, pollen counts tend to be highest in the morning, according to the ACAAI, so try to limit your child’s outdoor activity during this time.

Mold tends to increase again in September in cooler states, overlapping with part of the pollen season for weeds. But unlike pollen, mold tends to cause mostly lower respiratory symptoms like wheezing and coughing, Portnoy says.

Due to the combination of pollen, mold, and the cold virus, the last week of September is the peak of asthma season. More hospital admissions occur during this week than during any other week of the year, he says.


See the full guide via Everyday Health.

Check out today's pollen count.

Learn more about the Division of Allergy, Asthma and Immunology at Children's Mercy.