Pollen season in India is not what most of us think it is.
Every year, around February, some people in Delhi start sneezing. Most assume it is dust, or "something in the air", and wait it out. Sometimes it is dust. But often there is a specific plant responsible, a specific window when it peaks, and a specific month when it stops.
Based on published aerobiology studies, we built the India Pollen & Spore Calendarcovering 7 cities, and collected the questions we get most often in pollen FAQs for India. A few things the research told us that we did not expect.
Three things the research told us
India has two pollen seasons, not one
Unlike Europe, where spring dominates, India has a spring tree season and a separate post-monsoon season driven by weeds and grasses.
The monsoon does not give you a break
Pollen drops, but fungal spores spike. Cladosporium and Aspergillus fumigatus peak in the humidity. If your nose runs through July, it is probably spores, not pollen.
Pollen count is becoming a less useful number
Plants are under stress too. When CO₂ rises, they produce more of their defence chemicals, and these set off our immune system. Research shows the same effect across Parthenium, ragweed, birch and grass pollen. The grain itself is getting more potent, so our bodies are reacting to a stronger version of the same things they always have.
What is coming in the next few months, for your city
Bengaluru
The spring tree pollen peak (Peltophorum, Prosopis, Cassia) is winding down this month. But Parthenium does not stop. It persists through the monsoon at low levels and peaks again in September–October. Bengaluru rarely gets a true pollen-free window.
Kolkata
The spring tree pollen season (Peltophorum, Gulmohar, Neem) is winding down. What follows is not relief but the start of the fungal spore season. A 2019 study found 592 of 742 Kolkata allergy patients tested positive to at least one fungal extract. June through August is when those counts peak.
Delhi, Chandigarh, Jaipur
The monsoon will bring a genuine pollen break. But the post-monsoon weed and grass season (August–October) is equally intense, and is dominated by Cannabis, Parthenium and Chenopodium.
So what can you actually do?
Know your window. Use the Pollen & Spore Calendar it tells you exactly which months are high-risk for your city and which plants are driving them, so you can plan ahead.
Keep pollen out of your bedroom. Run an air purifier with HEPA 13 or 14 filters at night, and during the day where possible. Keep windows closed in the early morning, when most tree and grass pollen peaks. If you can, shower and change clothes when you get home. Pollen sticks to hair and fabric, and re-enters your home if you do not.
Do not confuse pollen season with monsoon relief. If your symptoms persist through July, switch your mental model from pollen to spores. Keep indoor humidity below 60%, where Aspergillus and Cladosporium growth slows down.
Close windows the moment a thunderstorm starts. Rain ruptures pollen grains into particles small enough to reach your lungs directly. This is why some people have their worst attacks on rainy days, not on clear ones.
If symptoms are severe or persistent, see an allergist. Sublingual immunotherapy (allergy drops or tablets) is now available in India for several common allergens, including grass pollen and Parthenium. It is one of the few options that addresses the cause, not just the symptoms.
This article is general information, not medical advice. If you have asthma, severe allergies, or persistent respiratory symptoms, consult a qualified allergist or pulmonologist.
Check your city's pollen window
Free, India-specific calendar covering 7 cities and the monsoon spore season.
Once you know your window, the practical countermeasures — filter selection, ventilation timing, laundry and bedding routines, and post-exposure rinses — are collected in the pollen and spore mitigation guide.
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