Houston's Worst Allergy Seasons: A Month-by-Month Guide for Sinus Sufferers

By: Dr. Madeleine Herman, MD

If you feel like your allergies never end in Houston, you're not imagining it.

Unlike many parts of the country that experience one or two distinct allergy seasons, Houston's warm climate, high humidity, and diverse vegetation create nearly year-round exposure to pollen, mold, and other airborne allergens.

For many people, this constant inflammation doesn't just cause sneezing and itchy eyes—it can also lead to chronic nasal congestion, sinus pressure, recurring sinus infections, and chronic sinusitis.

At SCENT Houston – Sinus Center & ENT Specialists of Houston, we treat patients throughout the year who struggle with persistent sinus symptoms that worsen as allergy seasons change. Understanding what allergens are most active each month can help you better manage your symptoms and recognize when it's time to seek expert care.

Why Is Houston One of the Worst Cities in the U.S. for Allergies?

Houston consistently ranks among the most challenging cities for allergy sufferers because of several factors:

• A warm climate that allows plants to pollinate for much of the year

• High humidity that encourages mold growth

• Frequent rainfall followed by rapid plant growth

• Long growing seasons

• Dense tree, grass, and weed populations

• Elevated mold spore counts after storms and flooding

  
  

Instead of having a single "allergy season," Houston experiences multiple overlapping pollen seasons. As one allergen declines, another often begins.

For people with allergic rhinitis or chronic sinus disease, this means inflammation may never fully resolve.

January Through March: Mountain Cedar and Tree Pollen Season

Many people assume allergy season begins in the spring, but for Houstonians, symptoms often start much earlier.

Mountain Cedar

Although mountain cedar trees are more common in Central Texas, their pollen frequently travels long distances into the Houston area.

Mountain cedar pollen is notorious for causing:

• Severe nasal congestion

• Sneezing

• Itchy eyes

• Runny nose

• Sinus pressure

• Fatigue

Many people refer to these symptoms as "cedar fever," even though it is not an infection.

Oak Pollen

As winter transitions into spring, oak trees begin releasing large amounts of pollen.

Oak pollen commonly causes:

• Congestion

• Facial pressure

• Postnasal drip

• Scratchy throat

• Worsening asthma symptoms

Other tree pollens—including elm, ash, maple, and pine—may also contribute during this time.

April Through June: Grass Pollen Takes Over

After tree pollen declines, grass pollen becomes the primary culprit.

Houston has numerous warm-season grasses that release pollen throughout late spring and early summer.

Common symptoms include:

• Persistent sneezing

• Itchy eyes

• Runny nose

• Nasal blockage

• Ear pressure

• Cough from postnasal drainage

  
  

Because grass pollen levels remain elevated for weeks, patients often notice worsening congestion that never completely improves.

For individuals with narrow sinus drainage pathways or chronic inflammation, this prolonged swelling may eventually interfere with normal sinus drainage.

To learn more, check out: https://www.scenthouston.com/sinus-services-houston

July and August: Humidity, Mold, and Lingering Allergens

Although pollen counts may be somewhat lower during the hottest months, many patients continue experiencing sinus symptoms.

Houston's extreme humidity creates ideal conditions for:

• Outdoor mold

• Indoor mold

• Dust mites

• Mildew

  
  

These allergens often trigger:

• Chronic congestion

• Thick mucus

• Reduced sense of smell

• Facial pressure

• Postnasal drip

Patients frequently assume they have another sinus infection when ongoing allergy inflammation is actually the underlying problem.

September Through November: Ragweed and Fall Mold Season

Fall brings another significant allergy season.

Ragweed

Ragweed pollen can travel hundreds of miles on windy days.

Symptoms often include:

• Sneezing

• Runny nose

• Congestion

• Itchy throat

• Sinus pressure

• Headaches

Mold

Houston's fall rains often lead to increased mold spore counts.

Outdoor mold commonly grows on:

• Leaves

• Mulch

• Grass

• Trees

• Soil

Indoor mold may increase after heavy rainfall or flooding.

For patients with chronic sinus disease, mold exposure can significantly worsen inflammation.

To learn more, check out: https://www.scenthouston.com/sinus-services-houston

December: Allergy Season Doesn't Always End

Unlike colder climates where hard freezes dramatically reduce pollen, Houston often experiences mild winters.

Tree pollen may begin increasing again before the holidays, restarting the annual cycle.

This is why many Houston residents feel like they are "always congested."

How Allergies Lead to Chronic Sinusitis

Many people think allergies and sinus infections are the same thing.

They are not.

Allergies cause inflammation inside the nose.

When inflammation becomes severe or persistent:

• Nasal tissues swell

• Sinus openings narrow

• Mucus becomes trapped

• Normal drainage slows

• Bacteria can multiply

Over time, repeated inflammation may contribute to chronic sinusitis.

This is why untreated allergies can eventually become much more than seasonal sneezing.

Allergy Symptoms vs. Sinus Infection: How to Tell the Difference

Common Allergy Symptoms

• Sneezing

• Itchy nose

• Itchy eyes

• Clear nasal drainage

• Seasonal congestion

• Symptoms that fluctuate with pollen counts

Common Sinus Infection Symptoms

• Thick yellow or green mucus

• Facial pain or pressure

• Fever (sometimes)

• Symptoms lasting longer than 10 days

• Worsening symptoms after initially improving

• Bad breath

• Tooth pain

• Reduced sense of smell

Because the symptoms often overlap, many people mistakenly treat allergies with repeated courses of antibiotics that offer little benefit.

An ENT evaluation can help determine the true cause.

To learn more, check out: https://www.scenthouston.com/sinus-services-houston

When Should You See an ENT?

If your symptoms continue long after allergy season ends, there may be more going on than seasonal allergies.

You should consider seeing an ENT if you experience:

• Nasal congestion lasting longer than 12 weeks

• Frequent sinus infections

• Difficulty breathing through your nose

• Chronic facial pressure

• Loss of smell

• Persistent postnasal drip

• Snoring related to nasal obstruction

• Symptoms despite allergy medications

An evaluation may include:

• Nasal endoscopy

• Allergy assessment

• In-office sinus CT imaging when appropriate

• Review of previous treatments

• Discussion of medical and procedural treatment options

Identifying the underlying cause is the first step toward lasting relief.

To learn more, check out: https://www.scenthouston.com/sinus-services-houston

How to Reduce Allergy-Related Sinus Problems

While no one can eliminate pollen from Houston's air, you can reduce its impact.

Helpful strategies include:

• Monitor local pollen and mold counts.

• Keep windows closed during high pollen days.

• Shower and change clothes after spending time outdoors.

• Use HEPA filters and replace HVAC filters regularly.

• Keep indoor humidity between 30% and 50%.

• Perform daily saline nasal irrigation during peak allergy seasons.

• Use allergy medications consistently as directed by your physician.

• Seek evaluation if symptoms persist despite treatment.

For many patients, combining environmental control with medical therapy leads to significant improvement.

Frequently Asked Questions

What is the worst allergy season in Houston?

There isn't just one. Houston experiences multiple allergy seasons throughout the year, including tree pollen in late winter and spring, grass pollen in late spring and summer, and ragweed and mold in the fall.

Can allergies cause chronic sinusitis?

Yes. Persistent allergy-related inflammation can block normal sinus drainage, increasing the risk of chronic sinusitis and recurrent sinus infections.

Why do my allergies never seem to end?

Houston's climate allows different allergens to dominate during different seasons. As one pollen season ends, another often begins, with mold and dust mites contributing year-round.

When should I worry that it's more than allergies?

If symptoms last longer than 12 weeks, recur frequently, interfere with sleep or daily activities, or don't improve with allergy treatment, it's time to be evaluated by an ENT specialist.

Don't Let Houston's Allergy Seasons Control Your Life

Living in Houston doesn't mean you have to accept constant congestion, sinus pressure, or recurring sinus infections as normal. Whether your symptoms are caused by allergies, chronic sinusitis, nasal polyps, or structural nasal blockage, the right diagnosis is essential for effective treatment.

At SCENT Houston – Sinus Center & ENT Specialists of Houston, Dr. Madeleine Herman specializes in diagnosing and treating allergy-related sinus disease using advanced nasal endoscopy, in-office CT imaging when indicated, and personalized treatment plans. From medical management and allergy care to minimally invasive balloon sinuplasty and endoscopic sinus surgery, our goal is to help you breathe easier throughout every Houston allergy season.

Still suffering after allergy season? Schedule a sinus evaluation at SCENT Houston and discover the underlying cause of your symptoms.

To learn more, check out: https://www.scenthouston.com/sinus-services-houston

Call us at 833-723-6863