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*Disclaimer: HeyAllergy® provides all clinical services furnished to patients in California, Florida, Texas, Illinois, Nevada, Pennsylvania. In New York, clinical services are furnished by Hey Allergy Medicine.
Real-time pollen data for Los Angeles — updated daily. Powered by board-certified allergists.
Los Angeles is home to several highly allergenic tree species. Coast live oak is the most widespread trigger, releasing heavy pollen loads from March through May. Olive trees, common in older LA neighborhoods and commercial landscaping, produce pollen from April through June that ranks among the most potent tree allergens in Southern California. Mulberry trees (now banned from new plantings in some areas due to their allergenic impact) still populate many established neighborhoods. Eucalyptus, ash, and sycamore round out the major tree pollen sources.
What makes LA different: Unlike cities with hard freezes, LA's mild winters mean some trees begin pollinating as early as late January — giving allergy sufferers one of the longest tree pollen seasons in the country.
Bermuda grass is the dominant grass allergen across Greater Los Angeles and is found in lawns, parks, golf courses, and highway medians throughout the region. Timothy grass, ryegrass, and bluegrass also contribute to the grass pollen load, particularly in irrigated suburban areas and the San Fernando Valley.
LA's year-round warm temperatures allow grass pollen to remain active far longer than in most U.S. cities. Even in December, Bermuda grass can produce measurable pollen on warm days.
Russian thistle (tumbleweed), mugwort, and ragweed are the primary weed allergens in Los Angeles. Russian thistle is especially problematic in the eastern parts of LA County and the Inland Empire, where dry, disturbed soil creates ideal growing conditions. Mugwort thrives along roadsides and vacant lots throughout the basin.
Santa Ana winds — hot, dry winds from the desert — can carry weed pollen from the inland valleys across the entire LA basin in a matter of hours, causing sudden spikes in symptoms for millions of residents.
Dust mites are a significant year-round trigger in Los Angeles, thriving in carpeted homes and bedding regardless of outdoor conditions. Mold spores are elevated near the coast and in older buildings with poor ventilation, particularly after winter rains. Pet dander (cat and dog) is the third major indoor allergen, affecting roughly 30% of allergy sufferers.
For many LA residents, the combination of outdoor pollen and indoor allergens means there is no true "allergy-free" period — making long-term treatment essential rather than optional.
While much of the country is still frozen, allergy season is already starting in Los Angeles. Cedar and juniper trees begin releasing pollen in January, and early-blooming trees like alder follow in February. Pollen counts are generally moderate, but sensitive individuals may notice symptoms — particularly on warm, dry days after Santa Ana wind events.
Top allergens: Cedar, juniper, alder
Severity: Low to moderate
Tip: Start taking antihistamines before symptoms appear if you have a history of spring allergies.
This is the worst period for allergy sufferers in Los Angeles. Oak, olive, mulberry, ash, and sycamore trees release massive amounts of pollen simultaneously. By late April, grass pollen from Bermuda and ryegrass begins overlapping with tree pollen, creating a double exposure that can overwhelm even mild allergy sufferers.
Top allergens: Oak, olive, mulberry, Bermuda grass
Severity: High to very high
Tip: Keep windows closed, shower after outdoor activity, and monitor daily pollen counts. This is the ideal time to start immunotherapy for long-term relief.
Tree pollen subsides, but grass pollen reaches its peak. Bermuda grass pollen can travel miles on the breeze and is difficult to avoid in a city with as much irrigated landscaping as Los Angeles. Dry summer conditions also increase airborne dust particles that irritate already-inflamed nasal passages. Smog levels peak during summer, compounding allergy symptoms for residents with both allergies and asthma.
Top allergens: Bermuda grass, Timothy grass, ryegrass
Severity: Moderate to high
Tip: Avoid outdoor exercise during midday when both pollen counts and air pollution peak. Use HEPA air purifiers indoors.
Ragweed, Russian thistle, and mugwort dominate the fall allergy landscape. September is often one of the worst months for LA allergies because weed pollen counts are high and Santa Ana winds can spike pollen levels without warning. A single Santa Ana event can push pollen counts from moderate to very high within hours.
Top allergens: Ragweed, Russian thistle, mugwort
Severity: Moderate to high (very high during Santa Ana events)
Tip: Track Santa Ana wind forecasts and premedicate on days when dry, hot winds are expected.
December is typically the mildest month for outdoor allergies in Los Angeles, though it never reaches zero. Winter rains wash pollen from the air temporarily, but rain also promotes mold spore growth — particularly in homes with poor drainage or ventilation. Indoor allergens like dust mites and pet dander become more prominent as residents spend more time inside.
Top allergens: Mold spores, dust mites, pet dander
Severity: Low (outdoor), moderate (indoor)
Tip: Use allergen-proof bedding covers and keep indoor humidity below 50% to control dust mites and mold.
Santa Ana winds are Los Angeles' most unpredictable allergy trigger. These hot, dry winds blow from the inland deserts and can spike pollen counts across the entire LA basin overnight. Check the weather forecast for Santa Ana warnings and take preventive antihistamines before symptoms hit. On Santa Ana days, keep all windows and doors sealed and run your air purifier on high.
Pollen counts in Los Angeles typically peak between 10 AM and 3 PM. If you run, bike, or exercise outdoors, schedule workouts for early morning or evening when counts are lower. Coastal areas — Santa Monica, Manhattan Beach, Venice — tend to have lower pollen counts than inland neighborhoods due to ocean breezes that push pollen away.
Many LA residents focus on outdoor allergens but neglect indoor air quality. Use a HEPA air purifier in your bedroom and main living spaces. Replace HVAC filters every 60–90 days with MERV-13 rated filters. If you have carpet, vacuum at least twice per week with a HEPA-equipped vacuum — or better yet, switch to hard flooring, which harbors fewer dust mites and traps less pollen.
Pollen clings to your hair, skin, and clothing. After spending time outdoors — especially during peak season — change clothes immediately, shower, and rinse your sinuses with a saline solution. Leave shoes at the door and wipe down pets that have been outside before they climb on furniture or bedding.
Over-the-counter antihistamines like Zyrtec, Claritin, and Allegra manage symptoms but don't treat the underlying cause of your allergies. If you've been taking allergy pills for years and still suffering, it's time to see a board-certified allergist. Sublingual immunotherapy (SLIT) — like HeyAllergy's HeyPak® drops — can retrain your immune system to stop overreacting to allergens, providing relief that lasts long after you stop treatment.
"I'm allergic to everything" is what many patients say before testing reveals they actually react to only 3–5 specific allergens. A comprehensive allergy blood test can identify your exact triggers, allowing your allergist to create a targeted treatment plan rather than a blanket approach. HeyAllergy makes this simple — book a virtual consultation and get your blood test ordered from the comfort of home.
March through May is typically the worst period for allergies in Los Angeles. Tree pollen from oak, olive, and mulberry peaks during these months, and by late April, grass pollen begins overlapping — creating a double exposure. September can also be severe due to weed pollen combined with Santa Ana wind events.
Yes. Unlike cities with hard freezes that create a clear "off season," Los Angeles' mild Mediterranean climate allows allergens to persist year-round. Outdoor pollen is present from January through November, and indoor allergens like dust mites, mold, and pet dander are active throughout the year.
Yes. HeyAllergy provides telemedicine appointments with board-certified allergists licensed in California. You can book a virtual consultation, have allergy blood tests ordered, receive a diagnosis, and start treatment — all without visiting a clinic. There is no waitlist and appointments are available quickly.
Sublingual immunotherapy involves placing customized allergen drops under your tongue daily. Over time, this retrains your immune system to stop overreacting to specific allergens. HeyAllergy's HeyPak® drops are personalized based on your allergy test results and formulated with allergens endemic to the Los Angeles area — including local tree, grass, and weed pollens. Most patients notice symptom improvement within 3–6 months.
HeyAllergy accepts Medicare and most major PPO health plans, including United Healthcare, Anthem Blue Cross, Blue Shield, Cigna, Aetna, Humana, Oscar, and Tricare. Telemedicine benefits vary by plan, so contact your insurance provider with HeyAllergy's Tax ID (85-0834175) to confirm your coverage.
General practitioners can prescribe antihistamines, but they aren't trained to diagnose specific allergen triggers or prescribe immunotherapy. HeyAllergy connects you directly with board-certified allergists and immunologists — specialists with advanced training in identifying the root cause of your allergies and creating long-term treatment plans, not just managing symptoms.
HeyAllergy's allergists order blood tests that screen for allergens specific to the Los Angeles region, including oak, olive, mulberry, and eucalyptus tree pollens, Bermuda and Timothy grass pollens, ragweed, Russian thistle, mugwort, dust mites, mold (Alternaria, Aspergillus, Cladosporium), and cat and dog dander. Your results determine which allergens are included in your personalized HeyPak® formula.
HeyAllergy has no waitlist. You can book an online appointment at a time that works for you and see a board-certified allergist via secure video consultation — typically within days, not weeks.
Los Angeles consistently ranks among the worst U.S. cities for allergies, and the reasons go beyond just pollen counts. The city's Mediterranean climate — warm, dry summers and mild, wet winters — creates conditions where allergen-producing plants thrive nearly year-round. There is no hard freeze to reset the cycle, which means LA residents never get the winter reprieve that people in colder climates rely on.
Geography compounds the problem. The Los Angeles basin is surrounded by mountains on three sides, trapping air pollution and pollen in a bowl-shaped formation. When Santa Ana winds blow from the desert, they push pollen and particulate matter across the entire basin, causing sudden symptom spikes for millions of residents. On these days, even people who normally manage their allergies well can experience breakthrough symptoms.
Urban landscaping choices also play a role. Many neighborhoods throughout LA are lined with highly allergenic trees — olive, mulberry, and ornamental grasses — that were planted decades ago before their allergenic potential was fully understood. Some cities in the region have since banned new mulberry plantings, but established trees continue producing heavy pollen loads each spring.
Los Angeles' well-known air quality challenges make allergies worse than pollen counts alone would suggest. Ground-level ozone and fine particulate matter (PM2.5) irritate nasal passages and airways, lowering the threshold at which allergens trigger symptoms. Research has shown that air pollution can make pollen grains more potent by causing them to release their allergenic proteins more readily.
For residents with both allergies and asthma — a common combination — the double exposure to pollen and poor air quality can be particularly dangerous. This is why allergists in Los Angeles often recommend monitoring both pollen counts and the Air Quality Index (AQI) when planning outdoor activities.
Getting to an in-person allergist appointment in Los Angeles means navigating some of the worst traffic in the country. Round-trip commute times of 60–90 minutes are common, and many traditional allergy clinics have weeks-long wait times for new patients. For allergy shot patients, the burden is even greater — requiring weekly or biweekly trips to a clinic for injections.
HeyAllergy eliminates these barriers with telemedicine-based allergy care. Los Angeles residents can see a board-certified allergist from home via secure video, have comprehensive blood allergy tests ordered to a nearby lab, and receive a personalized treatment plan — all without fighting LA traffic or sitting in a waiting room.
For patients who need immunotherapy, HeyAllergy's HeyPak® sublingual allergy drops replace clinic-based allergy shots with daily drops taken at home. The drops are customized based on your specific test results and the allergens that are endemic to the Los Angeles region. They're mailed directly to your door, with ongoing monitoring by your allergist through follow-up telemedicine visits.
Not everyone with occasional sneezing needs specialist care, but you should consider seeing a board-certified allergist if you experience allergy symptoms for more than 8 weeks per year, over-the-counter medications aren't providing adequate relief, your symptoms are affecting your sleep quality or work productivity, you have both allergies and asthma, you want to reduce your long-term dependence on allergy medications, or you're unsure what you're actually allergic to.
HeyAllergy's board-certified allergists specialize in diagnosing the specific triggers behind your symptoms and creating evidence-based treatment plans. Whether you need prescription nasal sprays, a customized immunotherapy plan, or a combination approach, our goal is long-term relief — not just symptom management.
