Photo by Dmitry Kropachev on Unsplash
If you’re planning a Japan trip for February through May and start noticing half the country sneezing, wearing wraparound glasses indoors, and checking their phones for a “pollen count” the way other countries check for rain — welcome to kafunsho season. Japan’s seasonal allergy problem is severe enough to have its own TV segments, dedicated drugstore aisles, and a vocabulary of products that can be baffling if you’ve never had to shop for them. Here’s what’s actually happening, when it peaks, and what’s worth buying.
Why Japan’s Pollen Season Catches Visitors Off Guard
The culprit is sugi, or Japanese cedar, a tree planted on a massive scale across the country after World War II for timber. Decades later, those forests have matured and now release enormous volumes of pollen every spring. An estimated 40% or more of the Japanese population has some degree of kafunsho (literally “pollen illness”), so when the season hits, it’s not a niche complaint — it’s a national event covered on morning news with the same seriousness as a typhoon track. Visitors who arrive in March expecting cherry-blossom season and nothing else are often surprised to find themselves with itchy eyes and a runny nose within a day or two outdoors.
When Does Cedar Pollen Peak? A Month-by-Month Forecast
Timing shifts by region and by year’s weather, but the general pattern is consistent enough to plan around:
- Kyushu and western Honshu: Cedar pollen can start as early as late January, peaking mid-February through mid-March.
- Tokyo, Kanto and Kansai: Pollen usually begins around February 10–20, with the heaviest days from late February through late March.
- Tohoku: Starts roughly two to three weeks later than Tokyo, peaking in late March to mid-April.
- Hokkaido: Cedar barely grows there, so cedar pollen is a non-issue — but birch (shirakaba) pollen takes over from late April into May.
- Hinoki (cypress) pollen: Follows cedar almost everywhere, typically peaking in April and tapering off by mid-May. If you’re still symptomatic after cedar season “ends,” this is usually why.
Warm, dry, windy days after a cold snap are consistently the worst — pollen counts spike noticeably on the first clear, breezy day following rain.
Checking the Daily Pollen Forecast
Locals don’t guess — they check a daily kafun forecast the same way they’d check the weather. The two most useful tools for visitors are:
- Weathernews’ “Pollen Navi” (花粉ナビ) app or site, which gives a color-coded count (少ない/multi/非常に多い — low to very high) by prefecture, updated several times a day.
- tenki.jp’s pollen page, which layers the forecast onto a regular weather app many visitors already use for trip planning.
Both are in Japanese, but the color scale (green = low, yellow = moderate, red/purple = severe) is easy to read without translation. If you’re also tracking train delays or planning day trips — say, after checking the shinkansen schedule for a regional excursion — it’s worth a quick glance before heading out on a high-pollen day.
What to Buy: Masks, Glasses and Nasal Sprays
Every drugstore chain — Matsumotokiyoshi, Sugi Drug, Cocokara Fine, Welcia, Tsuruha — dedicates significant shelf space to kafunsho goods from January through May, usually near the entrance. Hours are typically 9:00 or 10:00 to 21:00 or later, and station-front branches often stay open even later.
- Budget: A box of 30–50 high-filtration pollen masks (look for “花粉用” or high PFE/BFE percentages on the box) runs about ¥400–700. These are finer-mesh than standard surgical masks and fit closer to the face.
- Mid-range: Pollen-blocking glasses from opticians like JINS or Zoff (¥3,000–5,500) use a soft seal around the lens edge to stop pollen reaching the eyes — genuinely effective and sold at most mall locations. A static-resistant spray for coats and scarves (¥600–900, often called 花粉ブロックスプレー) stops pollen from clinging to outerwear fabric, which matters more than people expect since pollen rides indoors on clothes.
- Splurge: Air purifiers with pollen-rated HEPA filters for hotel or Airbnb rooms aren’t practical to buy for a short trip, but many business hotels and serviced apartments now list one as a room amenity during pollen season — worth checking when booking through Rakuten Travel, Jalan or Booking.com if you’re sensitive.
Also look for a small tube or cream (often labeled 花粉ブロック or ガードジェル) that you dab just inside the nostrils before going out — it traps pollen before it’s inhaled and is a favorite of Japanese commuters during peak weeks, priced around ¥700–900.
Eye Drops and Other Drugstore Remedies
Japanese eye drops are a category unto themselves, and the pollen-specific ones are worth knowing apart from general “refreshing” drops. Look for drops labeled 花粉 (pollen) or アレルギー (allergy) on the box — Rohto and Sante are the two biggest brands, and their allergy-formula lines (such as Rohto’s “Antibac” allergy range or Sante’s “Medical Guard”) contain mild antihistamine ingredients, priced roughly ¥700–1,300 for a 12–15ml bottle. Standard “cooling” eye drops without the allergy label will feel nice but won’t actually touch the itching.
For oral relief, Japan sells OTC antihistamines (look for 鼻炎 for rhinitis formulas) at the same drugstores, though dosing and active ingredients differ from what you may be used to at home — if you take a specific medication for allergies, it’s safer to bring your own supply from home rather than trying to match it on the shelf, since not every overseas brand name has a direct Japanese equivalent.
Regional Escapes: Where Pollen Is Lighter
If a trip lands squarely in peak season and you’re badly affected, geography can help more than any product. Okinawa has minimal cedar coverage and stays largely pollen-light through spring. Hokkaido is cedar-free, though its own birch pollen kicks in from late April — a trip timed for March or early April, like a visit to Asahiyama Zoo while its cold-weather exhibits are still in full swing, sidesteps both cedar and birch pollen entirely. Within Tokyo, pollen counts also tend to feel less oppressive in riverside, green neighborhoods with lower density and more open air circulation than the packed city center — a quieter stretch like Futako-Tamagawa is a reasonable half-day retreat if symptoms are flaring in the center.
Common Mistakes Visitors Make
- Assuming cherry blossom season and pollen season don’t overlap. They do — peak cedar pollen in Tokyo and Kyoto runs right through the early sakura weeks in March, so pack masks and drops alongside your hanami plans, not instead of them.
- Buying a regular surgical mask instead of a pollen-rated one. Standard masks block droplets, not the much smaller pollen particles as effectively — check the box for a pollen-specific filtration claim.
- Not changing clothes or washing hair after a high-pollen day. Locals rinse hair and swap jackets at the door specifically to stop carrying pollen indoors overnight, which is why symptoms often feel worse at night than people expect.
- Ignoring hinoki season. Travelers who tough out cedar season in March sometimes assume they’re clear by April, only to get hit by cypress pollen through May — if you’re still reacting into late spring, it’s not a new problem, just the second wave.
None of this should derail a spring trip — it’s a manageable, well-understood seasonal fact of life that millions of residents navigate every year with a mask, a bottle of eye drops, and a daily glance at the forecast app. Pack light defenses, check the pollen count the way you’d check rain odds, and the season becomes a minor footnote rather than a surprise.