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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 San Diego — updated daily. Powered by board-certified allergists.
San Diego's mild winters mean tree pollen season starts earlier than most U.S. cities. Acacia and eucalyptus trees begin releasing pollen as early as December and January, followed by ash, mulberry, olive, oak, sycamore, and walnut trees from February through May. Olive trees are particularly significant in San Diego — widely planted throughout neighborhoods and commercial landscaping, they produce large quantities of highly allergenic pollen that can create visible clouds and trigger severe reactions even at moderate counts.
Oak pollen peaks in March and April and is the dominant spring allergen. San Diego's many eucalyptus groves — non-native trees planted extensively in the early 20th century — add a unique allergen layer that distinguishes the city from other California metros. Pine pollen, while generally less allergenic, contributes to the overall spring pollen load in communities adjacent to Torrey Pines and other forested areas.
Bermuda grass is San Diego's dominant grass allergen, thriving year-round in the city's warm, semi-arid climate. Ryegrass, Kentucky bluegrass, and oat grass are additional contributors. Grass pollen peaks from May through July but can remain elevated through September — a longer grass season than many coastal cities. San Diego's extensive parks, golf courses, athletic fields, and residential lawns across communities from La Jolla to Chula Vista are constant grass pollen sources.
The transition from tree to grass pollen in April and May creates a challenging overlap period when both allergen types are elevated simultaneously.
Ragweed, while less prevalent in San Diego than in Midwest and East Coast cities, still affects sensitive individuals, particularly in inland areas like El Cajon, Santee, and Escondido. Sagebrush is a more significant fall allergen in San Diego, especially in communities adjacent to natural chaparral habitat. Russian thistle (tumbleweed), pigweed, and lamb's quarters contribute to the fall weed pollen load.
San Diego's canyon ecosystems — found throughout the city from Mission Trails to Balboa Park's perimeter to neighborhoods like University City and Clairemont — harbor dense weed growth that releases concentrated pollen clouds, particularly after rain events break dry spells.
Santa Ana winds are San Diego's unique allergy wildcard. These hot, dry winds blow from the inland deserts through mountain passes and into coastal San Diego, carrying allergens from as far away as Arizona and Nevada. During Santa Ana events, residents may be exposed to pollen and particulate matter from plants they don't encounter locally. Santa Ana winds also stir up dust, mold spores, and existing local pollen, preventing natural settling and creating high-concentration allergen events.
Santa Ana conditions are most common from October through March but can occur as late as May. These wind events are among the most challenging days for San Diego allergy sufferers.
Dust mites are a significant year-round allergen in San Diego. Unlike many U.S. cities where dust mite populations are seasonal, San Diego's consistent mild humidity and temperatures allow dust mites to reproduce year-round. Dust mites are particularly problematic from October through March when San Diegans spend more time indoors. Mold grows on outdoor surfaces year-round and can accumulate indoors, particularly in coastal communities with marine layer moisture exposure. Pet dander adds to the constant indoor allergen load.
San Diego's allergy season starts earlier than most cities. Acacia trees bloom as early as January, producing bright yellow flowers and highly allergenic pollen. Eucalyptus trees — planted extensively throughout the city — begin releasing pollen in winter. Ash and juniper trees start pollinating by February. Meanwhile, dust mite concentrations peak during winter months as residents spend more time indoors with windows closed. The marine layer can trap allergens close to the ground in coastal communities.
Top allergens: Acacia, eucalyptus, ash, juniper, dust mites
Severity: Low to moderate (outdoor), moderate to high (indoor/dust mites)
Tip: San Diego's "mild winter" doesn't mean allergy-free. If you're congested from January through March, winter tree pollen or dust mites may be the cause. Encase mattresses and pillows in dust-mite-proof covers and wash bedding in hot water weekly.
This is San Diego's most intense outdoor allergy period. Oak pollen peaks in March and April, olive trees produce heavy pollen loads from March through May, and mulberry, sycamore, and walnut trees add to the mix. Grass pollen begins rising by April, creating an overlap with late tree pollen. Balboa Park, Torrey Pines, Mission Trails, and the city's extensive canyon systems become concentrated pollen sources.
Top allergens: Oak, olive, mulberry, sycamore, ash, early Bermuda grass
Severity: High to very high
Tip: Olive tree pollen is extremely potent — if your allergies are worst during March and April and you live near olive trees (common in older San Diego neighborhoods), get tested specifically for olive pollen. It's one of the most underdiagnosed triggers in Southern California.
Grass pollen peaks in early summer, with Bermuda grass the primary culprit. San Diego's June Gloom (persistent marine layer) brings coastal moisture that can elevate mold spore counts in beach communities from Ocean Beach to Carlsbad. By mid-summer, grass pollen begins declining, but outdoor activities increase dramatically, leading to more allergen exposure. Summer is the most comfortable season for many San Diego allergy sufferers, though it's far from symptom-free.
Top allergens: Bermuda grass, ryegrass, mold spores (coastal), dust
Severity: Moderate
Tip: June Gloom isn't just gloomy — the marine layer moisture promotes mold growth on outdoor surfaces and can seep into poorly ventilated homes. If you live within a mile of the coast, run a dehumidifier during June and July to control indoor mold.
Fall brings the combination of weed pollen and Santa Ana wind events — arguably San Diego's most unpredictable allergy period. Sagebrush, ragweed, and Russian thistle release pollen from August through November. Santa Ana winds, most common from October onward, carry allergens from inland deserts and stir up local pollen, dust, and mold. Canyon vegetation releases concentrated pollen clouds after fall rain events break the dry summer spell.
Top allergens: Sagebrush, ragweed, Russian thistle, Santa Ana wind particulates
Severity: Moderate to high (spiking to very high during Santa Ana events)
Tip: Santa Ana wind days are San Diego's worst allergy days. When weather forecasts predict Santa Ana conditions, close all windows, run HEPA air purifiers, and premedicate. Check air quality indices — if wildfire smoke accompanies the winds, the combination is especially harmful for asthma sufferers.
December is a brief transition period — the last weed pollens fade, but early-blooming acacia and eucalyptus trees begin their cycle. Santa Ana wind events can still occur. Indoor allergens become more prominent as temperatures drop slightly and homes are sealed more often. Holiday travel can expose residents to different allergen profiles.
Top allergens: Eucalyptus, acacia, dust mites, indoor mold
Severity: Low to moderate
Tip: December is San Diego's closest thing to an allergy break — use this window to start HeyPak® sublingual immunotherapy and build tolerance before spring pollen arrives.
Many people move to San Diego expecting the ocean air to eliminate allergy problems. The reality: San Diego has the most reported allergy cases of any city in the Southern California region. The combination of canyon ecosystems harboring dense vegetation, non-native trees (olive, eucalyptus) planted throughout neighborhoods, Santa Ana winds carrying allergens from Arizona and Nevada, and year-round dust mite populations creates a complex allergen environment. If you moved to San Diego and developed allergies you never had before, you're not alone — and you're not imagining it.
Santa Ana winds are San Diego's most dangerous allergy trigger. These hot, dry winds blow from the inland deserts and can carry pollen, dust, and particulate matter from hundreds of miles away into coastal neighborhoods that normally have relatively clean air. During Santa Ana events, close all windows, run HEPA air purifiers, and keep your car windows up with AC on recirculate. If you have asthma, carry your rescue inhaler. When wildfires accompany Santa Ana conditions, the combination of smoke particulates and pollen is especially harmful — consider an N-95 mask for outdoor exposure.
San Diego's canyon systems run through the heart of the city — from Mission Trails Regional Park through neighborhoods like University City, Clairemont, Linda Vista, and surrounding Balboa Park. These canyons harbor dense chaparral, weeds, grasses, and trees that produce concentrated pollen. Homes bordering canyons can experience significantly higher allergen exposure than homes a few blocks away. If you live canyon-adjacent and have allergy symptoms, this proximity is a major factor. Keep canyon-facing windows closed during peak pollen hours (morning) and consider HEPA filtration in rooms facing the canyon.
Olive trees are planted extensively throughout older San Diego neighborhoods, commercial areas, and public spaces. They produce extremely allergenic pollen from March through May and are one of the most underdiagnosed allergy triggers in Southern California. The pollen can create visible clouds and travel significant distances. If your worst allergy symptoms coincide with olive tree blooming, targeted testing for olive pollen is essential. Many patients who've been told they have "oak allergies" may actually be primarily reactive to olive pollen — and the treatment approach differs.
Unlike cities with harsh winters where dust mites die off seasonally, San Diego's mild temperatures allow dust mite populations to thrive 365 days a year. Dust mites are often the hidden driver behind chronic, year-round nasal congestion and morning symptoms that don't seem to follow a seasonal pattern. Encase pillows and mattresses in dust-mite-proof covers, wash bedding weekly in hot water (130°F+), and maintain indoor humidity below 50%. If your symptoms are worst in the morning or at night, dust mites in bedding are the most likely cause.
San Diego's overlapping allergen seasons mean OTC antihistamines are often fighting multiple triggers simultaneously without addressing any of them effectively. HeyAllergy's board-certified allergists can identify your specific triggers through blood testing — whether it's olive pollen, dust mites, Bermuda grass, or canyon-adjacent chaparral weeds — and create a personalized HeyPak® sublingual immunotherapy plan. Most patients notice improvement within 3–6 months. Book a telemedicine consultation from anywhere in San Diego County — no clinic visit needed, no waitlist.
March through May is typically the worst period, when oak and olive tree pollen peaks and overlaps with early grass pollen. However, Santa Ana wind events (most common October through March) can create severe allergy days at any point during the fall and winter. September through November brings weed pollen plus wind-driven allergen surges.
Yes. San Diego's mild climate means there's no hard freeze to end pollen season, trees begin pollinating as early as January, and dust mites thrive year-round. The city's warmth extends grass pollen through September, and Santa Ana winds create episodic allergen surges from fall through spring. There's no truly allergy-free month in San Diego.
San Diego has the most reported allergy cases in the Southern California region. Santa Ana winds carry allergens from Arizona and Nevada deserts into coastal areas. The city's canyon ecosystems harbor dense pollen-producing vegetation, non-native trees like olive and eucalyptus are highly allergenic, and dust mites thrive year-round in the mild climate. Living near the ocean doesn't protect against these factors.
Santa Ana winds are hot, dry winds that blow from inland deserts through mountain passes into coastal San Diego. They carry pollen, dust, and particulate matter from hundreds of miles away, stir up local allergens, and prevent natural settling of airborne particles. During Santa Ana events, allergy symptoms can spike dramatically — even for people who normally do well in San Diego.
Yes. HeyAllergy provides telemedicine appointments with board-certified allergists licensed in California. You can book a virtual consultation, have allergy blood tests ordered at a local lab, receive a diagnosis, and start treatment — all without visiting a clinic. No waitlist.
HeyAllergy's HeyPak® sublingual immunotherapy drops are customized based on your blood allergy test results and formulated with allergens specific to the San Diego region — including oak, olive, Bermuda grass, sagebrush, dust mites, and mold. You place drops under your tongue daily at home. Over 3–6 months, your immune system builds tolerance, reducing symptoms and medication dependence.
HeyAllergy accepts Medicare and most major PPO health plans, including United Healthcare, Health Net, Anthem Blue Cross, Blue Shield, Cigna, Aetna, Humana, Oscar, and Tricare. Telemedicine benefits vary by plan — contact your insurance provider with HeyAllergy's Tax ID (85-0834175) to confirm your specific coverage.
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. Available for residents throughout San Diego County including La Jolla, Chula Vista, Escondido, Oceanside, and Carlsbad.
San Diego's reputation as America's finest city attracts thousands of new residents every year — many of whom expect the coastal climate to be a haven from allergies. The reality is strikingly different. San Diego has the most reported allergy cases of any city in the Southern California region. The combination of factors that create this paradox is unique: Santa Ana winds carrying allergens from Arizona and Nevada deserts, canyon ecosystems harboring dense pollen-producing vegetation throughout the urban core, extensive plantings of highly allergenic non-native trees, and a mild climate that supports year-round dust mite populations and extends pollen seasons well beyond what northern cities experience.
For San Diego's 1.4 million residents, understanding these factors is the first step toward effective allergy management — because the strategies that work in other cities may not address San Diego's distinctive allergen profile.
Santa Ana winds are the defining feature of San Diego's allergy environment. These hot, dry winds originate in the Great Basin and Mojave Desert, gaining speed as they funnel through mountain passes before descending into coastal communities. They carry pollen from plants that don't grow locally, dust from desert soils, and airborne particulates that can travel hundreds of miles.
When Santa Ana conditions develop — most commonly from October through March, but possible into May — the air quality in San Diego can change dramatically within hours. Residents in normally clean-air coastal communities from La Jolla to Coronado suddenly find themselves exposed to allergen concentrations comparable to inland desert cities. These wind events also prevent natural pollen settling, keeping local allergens airborne longer and at higher concentrations than calm days. When wildfires accompany Santa Ana conditions, the combination of smoke particulates and pollen creates especially dangerous conditions for asthma and allergy sufferers.
Unlike most major cities where nature is confined to designated parks, San Diego's canyon systems weave through the urban fabric like green arteries. Mission Trails Regional Park, the canyons surrounding Balboa Park, and the ravines threading through neighborhoods like University City, Clairemont, Linda Vista, North Park, and Del Cerro create a network of wild vegetation in the middle of the metro area.
These canyons harbor dense chaparral, sagebrush, wild grasses, and weeds that produce concentrated pollen loads. After rain events — which often follow long dry spells — canyon vegetation responds with explosive growth and pollen release. Homes bordering these canyons can experience allergen concentrations significantly higher than homes just a few blocks away, creating hyperlocal allergy zones that affect some residents far more than their neighbors.
San Diego's landscaping history has created an unusual tree allergen profile. Olive trees, eucalyptus groves, and acacia trees were planted extensively throughout the city over the past century for their aesthetic value and drought tolerance. All three are highly allergenic. Olive trees are particularly problematic — they produce massive amounts of extremely potent pollen from March through May, creating visible clouds that drift through neighborhoods. Many San Diego residents have olive trees on their property or within a block of their home without realizing they're living next to a major allergen source.
Eucalyptus groves — remnants of early 20th-century planting projects — are found across the county from Balboa Park to suburban Escondido. These trees produce pollen during winter months when most residents don't expect tree allergens. The combination of native and non-native tree species means San Diego has an unusually long tree pollen season, starting in January and extending through May.
San Diego's famous June Gloom — the persistent marine layer that blankets coastal communities from late May through early July — has allergy implications that residents often overlook. The cool, moist air promotes mold growth on outdoor surfaces, fences, building exteriors, and in poorly ventilated homes. The marine layer can also trap allergens close to the ground, creating concentrated exposure zones in low-lying coastal areas from Ocean Beach to Cardiff.
For residents who live within a mile of the coast, this moisture effect makes mold a more significant allergen than it is for inland communities. Running dehumidifiers during June and July, ensuring bathroom and kitchen ventilation, and keeping outdoor-facing surfaces clean can help manage this coastal-specific mold exposure.
San Diego County spans over 4,200 square miles — from Oceanside in the north to the Mexican border in the south, and from the coast to the mountains and desert communities of East County. Driving from Escondido to a specialist in downtown San Diego can take over an hour in traffic. Traditional allergy clinics often have extended wait times, and the sprawling geography makes weekly allergy shot appointments impractical for many residents.
HeyAllergy eliminates these barriers. Residents from La Jolla to Chula Vista to Carlsbad to El Cajon can see a board-certified allergist from home via secure video consultation. Blood allergy tests can be ordered to a convenient local lab anywhere in the county, and a personalized treatment plan — including HeyPak® sublingual immunotherapy drops formulated for San Diego's specific allergen profile — can begin without a single in-person visit.
HeyPak® is delivered to your door and taken daily under the tongue. The drops are customized based on your blood test results, targeting the specific mix of native and non-native allergens causing your symptoms — whether that's olive pollen, canyon sagebrush, Bermuda grass, dust mites, or the desert particulates that arrive with Santa Ana winds. No needles, no I-5 traffic, no waitlist.
If you moved to San Diego and developed allergies you never had before, if your symptoms spike during Santa Ana wind events, if you live near a canyon and have chronic congestion, if over-the-counter medications aren't providing adequate relief, if you suspect olive or eucalyptus trees near your home are contributing to your symptoms, if your allergies affect you year-round rather than just seasonally, or if you have both allergies and asthma, it's time to see a board-certified allergist.
HeyAllergy accepts Medicare and most major PPO health plans, making expert allergy care accessible for residents throughout San Diego County.
