Wasabi farmers in Japan fear shrinking production amid climate change
At a buckwheat soba noodle restaurant in Tokyo, the signature noodle dish is served with a piece of raw wasabi, for diners to grind little pieces into the dipping sauce. But due to dwindling supplies, the restaurant fears it may not be able to serve fresh wasabi in the future.
"In the past, we served all the cold soba noodles with a piece of raw wasabi, but now we can no longer do that… due to insufficient supply of wasabi, we had to change our menu (to make raw wasabi only available for certain dishes)," said Norihito Onishi, manager of soba noodle restaurant chain Sojibo.
While the supply of wasabi was relatively sufficient at the time when the restaurant opened 30 years ago, Onishi said during the past decade he has faced situations where he had difficulties securing a stable supply of raw wasabi, attributing the shortage partly to climate change.
At the other end of the supply chain, wasabi farmer Masahiro Hoshina agrees.
"Recently, the power of a typhoon feels totally different from before due to global warming. It’s getting stronger," said the 70-year-old farmer, from Okutama, a mountainous area to the west of Tokyo.
Hoshina has started worrying about his wasabi plants ahead of each rainy season, since Typhoon Hagibis hit Japan in 2019, flushing away many crops belonging to his neighbours. The wasabi harvest in Okutama was slashed by nearly 70% the following year according to local official data.
It took the farmers three years to recover from that disaster as wasabi plants, that grow in clear flowing water, need careful cultivation and around 18 months to reach maturity, according to Hoshina, who is also the head of the local wasabi farmers' association.
"Global warming can be considered as one of many factors that are affecting wasabi production. When the water temperature rises, the amount of oxygen decreases which affects the growth of wasabi. The decreasing snow cover indirectly results in animals creating more damage to wasabi fields, which also discourages farmers. In addition to that, damages from flooding (due to rainstorms) become more frequent and they hit farmers as well," explained Kyoko Yamane, an Associate Professor of Applied Biological Sciences at Gifu University.
This comes as a rapidly ageing population is threatening the sustainability of many traditional livelihood practices in Japan, including wasabi cultivation.
“I’m also concerned that more farmers will quit as they are getting older, and fewer people will grow it," said Hoshina.
Japan's Ministry of Agriculture's latest data in 2020 shows that the production of wasabi has declined dramatically by more than half, compared to levels in 2005.
"If this unstable supply of wasabi persists in the future…we will face a situation where we need to come up with other ways to overcome the problem so that we don’t end up not serving raw wasabi at all," said Onishi.