Allergies In San Antonio: Everything To Know

Written by Hannah Ward
Published: February 21, 2023
Share this post on:


Listen to Article

Ranked as one of the top five allergy capitals in the US, San Antonio, Texas is a challenging place for allergy sufferers to live. In fact, you may already know that cedar pollen is one of the worst allergens in the area, causing the well-known “cedar fever”. But when is the peak allergy season and which other plants and trees are triggers? Read on to learn everything about allergies in San Antonio, including some tips on how to ease your symptoms.

When is Allergy Season in San Antonio?

Due to it’s hot climate the allergy season lasts for a long time in San Antonio. However, although the allergy season lasts almost all year round, it peaks during the fall and the winter. According to the Asthma and Allergy Foundation of America, San Antonio is ranked fifth in the list of allergy capitals from 2022. Of all the cities in Texas only McAllen ranks higher in the number three spot. San Antonio moves up one position to four during the fall but drops down to 13th in the spring.

San Antonio allergy season peaks in fall and winter
Although the allergy season lasts almost all year round in San Antonio, it peaks during the fall and the winter.

©Sean Pavone/

How Do Plants Cause Allergies?

Before we talk about which plants cause allergies in San Antonio it is important to also explain how they cause them. Pollen is produced by the male parts of the plant to pollinate the female plants and trees. Pollen is made up of tiny microscopic grains which can be transported for hundreds, even thousands, of miles by the wind as well as shorter distances by birds and insects.

For many people pollen is completely harmless and their body does not react to it. However, for allergy sufferers it becomes known as an “allergen”. An allergen is a substance that the body mis-identifies as being harmful to it. When this happens an immune response is triggered as the body attempts to destroy and drive out the “harmful” particles – thereby creating the symptoms that we know so well – runny nose, scratchy throat, watery eyes, sneezing, and even a rash (hives).

Plants that Cause Allergies in San Antonio (By Season)

There are vast quantities of plants that can cause allergies, even in just the San Antonio area. However, they can be grouped into three categories — weeds, grasses, and trees. Let’s take a closer look at these common allergens on a season-by-season basis.


Spring, the time when the plants begin to bud and the temperatures start to rise. However, spring also sees the beginning of the tree pollen season in early March. Lasting until May, trees that pollinate during this period include Arizona ash, hackberry, live oak, and willow trees.

Live oak is the most significant spring problem for allergy sufferers. Live oak is not pollinated by insects as it does not produce flowers. Therefore, it relies on the wind for pollination instead. Live oak produces fine yellow, dust-like particles of pollen which can typically be seen covering cars and sidewalks.

Live oak is a spring problem for allergy sufferers in San Antonio
Live oak is the most significant spring problem for allergy sufferers in San Antonio producing tree pollen spread by the wind.

© Snydacker


As we move into the full heat of the summer it is time for allergy sufferers to beware of grass pollen. Just like live oak, grass pollen is typically spread by the wind. This means that in both spring and summer the worst conditions for allergies are dry, windy days as this is when there will be a lot of pollen blowing around. Bahia grass and Bermuda grass are the main triggers during this season. Bahia grass is native to South America and Mexico, but is now widespread in North America too, while Bermuda grass is an introduced species — not native to the US at all. Both are tolerant to drought and are persistent growers, thriving in harsh conditions.


The beginning of fall marks the start of the weed pollen season and there is one main allergen during this season — ragweed. Ragweeds are several species of plants within the Asteraceae family group — the Aster family. Although they typically only pollinate between October and November in San Antonio, ragweeds are highly prolific and can produce anything up to one billion pollen particles from one plant in every year.

Ragweed is a serious weed allergen
Ragweed is the main fall allergen in San Antonio, producing up to one billion pollen particles from one plant in every year.

© Carol Cenusa


Finally, we move onto winter and the second part of San Antonio’s peak allergy season. Although we’ve already talked about the tree pollen season in the spring there is one rather significant exception — the mountain cedar. Also known as Ashe juniper, the mountain cedar pollinates between December and February. We briefly mentioned “cedar fever” earlier and this is a colloquial phrase for the allergic reactions that these trees cause. However, despite the phrase, there is actually no fever involved at all. Instead, symptoms are generally quite severe and include headaches, constant sneezng, fatigue, and a burning throat.

Juniperus ashei, Ashe juniper, mountain cedar
In winter, the mountain cedar (Ashe juniper) causes severe allergic reactions such as headaches, constant sneezing, fatigue, and a burning throat.

©micklpickl at Flickr, CC BY-SA 2.0 , via Wikimedia Commons – License

How to Alleviate Allergy Symptoms

Although you may think that you’ve got no option but to suffer silently through the allergy season, there are actually a few things that you can do to ease your symptoms. Although the two main categories are prevention and medication which we’ll explore in more detail shortly, you can also take an allergy test. By taking an allergy test you can find out exactly which allergies are your triggers and take steps to avoid them — for example it might be tree pollen in general that you are allergic to, or maybe a specific type of grass or weed pollen.


  • Medical advice: As always, speak to your doctor first as they will be able to offer you tailored advice and may be able to offer you medication that you cannot get over the counter.
  • Oral antihistamines: These are often available over the counter and aim to relieve the common allergy symptoms. There are several types available and they generally contain either loratadine, cetirizine, or fexofenadine.
  • Nasal sprays: Nasal sprays are anti-inflammatory medication and can be used to treat symptoms that range from moderate to severe.


  • Stay indoors: Although it’s impractical to stay indoors all the time it is a good idea to check the pollen count and stay indoors if it is particularly high.
  • Avoid gardening: It’s advisable to avoid doing outdoor chores such as mowing the lawn, weeding, or trimming trees as these tasks can bring you into contact with pollen in the air as well as stir the particles up more. However, if you do need to do gardening then you should wash your clothes immediately after as the pollen will be clinging to your clothes – the same is advised if you’ve been outdoors while the pollen count is high.
  • Close your windows: Surprisingly, something as simple as keeping your doors and windows closed can go a long way to preventing pollen from entering your home.
  • Keep your home clean: Even if you keep your windows and doors closed as much as possible some pollen will still enter your home. Therefore, regular vacuuming will remove and that has landed on your carpets and upholstery. However, you can also take it a step further and keep the air in your house clear by using a dehumidifier or an air purifier with powerful filter such as a HEPA filter (high-efficiency particulate air filter).

The Featured Image

Man with allergies
Man with allergy sneezing into handkerchief with blooming trees in background.

Share this post on:
About the Author

I have been writing professionally for several years with a focus on animals and wildlife. I love spending time in the outdoors and when not writing I can be found on the farm surrounded by horses, dogs, sheep, and pigs.

Thank you for reading! Have some feedback for us? Contact the AZ Animals editorial team.