Izu wasabi: the stone-terraced fields of Amagi and where to taste the real thing
The Amagi highlands grow some of Japan's finest fresh wasabi in stone-terraced fields fed by spring water, a system recognised as a Globally Important Agricultural Heritage System. How the tatami-ishi fields work, how to see Ikadaba and Joren Falls, and how to eat fresh wasabi properly.
- Best place to see the fields
- Ikadaba (car) and Joren Falls (bus)
- By bus
- Tokai Bus from Shuzenji Station towards Kawazu, stop Joren-no-taki
- What to eat
- soba with fresh wasabi, wasabi-don, wasabi-zuke
- Etiquette
- the terraces are working farmland: look, do not enter
Most of the green paste served with sushi outside Japan has never been near a wasabi plant. Real wasabi is a root-like stem that grows in cold running water, and some of the best in Japan comes from the mountains in the middle of the Izu Peninsula. In the valleys below Mount Amagi, farmers grow it in terraces built from layers of stone, flooded by spring water all year round. The system is old enough, and unusual enough, to be listed by the United Nations' Food and Agriculture Organization as a Globally Important Agricultural Heritage System. This guide explains how the fields work, where you can see them, and how to taste fresh wasabi the way it is eaten in Izu.
A plant that needs cold, clean, moving water
The wasabi grown in Izu is sawa-wasabi, "stream wasabi", the kind raised in water rather than in soil. It is a native Japanese plant of the cabbage and mustard family. It grew wild along mountain streams long before anyone farmed it, and according to JETRO, Japan's trade promotion agency, people began cultivating it more than 400 years ago. The same source gives its ideal water temperature as roughly 10 to 15°C all year, which is why it thrives where spring water comes out of the ground at a steady temperature, cool in summer and never frozen in winter. Shizuoka and Nagano prefectures together grow more than 90% of Japan's sawa-wasabi.
The heat of wasabi is not like the heat of chilli. It comes from compounds released only when the plant's cells are crushed, which is why fresh wasabi is grated just before eating and loses its sharpness within minutes. The result is a sharp, aromatic heat that goes up the nose and fades quickly, with a sweetness behind it that tube paste does not have.
The tatami-ishi fields: farming with stone
What makes Shizuoka's system special is the way the fields are built. In a tatami-ishi ("stacked stone") field, the farmers clear a mountain stream and build terraces with large stones at the bottom, progressively smaller stones above them and sand on top. Spring water enters at the top of each terrace and seeps down through the layers. The stones filter the water and keep it moving, so the roots get oxygen and the water stays cool and clean. JETRO dates the method to around the middle of the Meiji period (1868–1912) and credits its development to the area that is now Izu City.
The Ministry of Agriculture, Forestry and Fisheries describes the practice as relying on the nutrients in the spring water, with as little fertiliser or pesticide as possible. Japan listed "Traditional Wasabi Cultivation in Shizuoka" as a national agricultural heritage system in March 2017, and the FAO added it to its global list in March 2018. The listing covers the wasabi areas of Shizuoka City as well as those of Izu.
Where to see the fields
Ikadaba (Jizodo, Izu City). The best-known view is the Ikadaba wasabi fields, in the hills of the Jizodo district on the Amagi side of Izu City. The agriculture ministry describes Ikadaba as one of the largest cultivation areas in the Izu region, with a wide view over tatami-ishi terraces, and notes that it was chosen as one of Shizuoka's ten best terraced landscapes. A narrow road runs past the terraces, and a small parking area and bridge give the classic view down the valley. Ikadaba is a working farm, not a park: look from the road, do not step on the terraces, and do not touch the plants or the water channels. Getting there realistically needs a car or a taxi from Shuzenji, as public transport does not serve the valley in a way that is practical for a short visit.
Joren Falls (Yugashima, Izu City). The easiest place to see wasabi growing is below Joren Falls, the waterfall on the Kano River that we describe in our guide to Izu's volcanic sites. A stairway leads from the road down to the falls, and terraced wasabi beds sit along the stream beside the path. Stalls and shops near the top sell fresh wasabi, pickles and other wasabi products. Joren Falls is on the Tokai Bus route over the Amagi Pass between Shuzenji Station and Kawazu; ask for the "Joren-no-taki" stop.
Some farms and local operators in the Amagi area offer guided visits, harvesting or pickle-making sessions; the ministry's own leaflet mentions e-bike tours and wasabi harvesting. These change from year to year, so check with the Izu City tourist association or your inn before you go.
How to eat fresh wasabi
- Grate it at the table. Use a fine grater, traditionally one covered with sharkskin. Trim the top where the leaves joined the stem, then grate that end in slow circles. Grate only what you will eat in the next few minutes.
- Put it on the food, not in the soy sauce. Locals place a little grated wasabi directly on sashimi or a slice of meat, then dip lightly in soy sauce. Stirring it into the soy sauce dulls the aroma.
- Try the classic Amagi dishes. Restaurants around Shuzenji and the Amagi Pass serve soba noodles with a whole stem of wasabi and a grater on the side, and wasabi-don, a bowl of hot rice topped with bonito flakes, a dash of soy sauce and freshly grated wasabi. It sounds too simple to be good; it is excellent.
- Look for wasabi-zuke. The stems and leaves are chopped and pickled in sake lees to make wasabi-zuke, a pungent side dish sold all over the peninsula and a good souvenir.
Buying wasabi to take home
A fresh stem keeps for a couple of weeks in the refrigerator if it is wrapped in damp paper and the water is changed often, which makes it a realistic gift for someone in Japan but not for a long flight home. Wasabi-zuke, dried wasabi products and wasabi-flavoured snacks travel better. Many tubes and sachets labelled "wasabi", in Japan and abroad, contain mostly horseradish with some green colouring; if you want the real thing, read the ingredients list and look for products that list hon-wasabi (true wasabi) first.
Putting it together
A wasabi day fits naturally with a stay in Shuzenji. Take the bus up to Joren Falls in the morning, walk down to the falls and the wasabi beds, eat soba or wasabi-don near the pass, and return to Shuzenji for a bath in the afternoon; our guide to Shuzenji covers the town and its hot springs. With a car, add Ikadaba on the way. If you are coming from Tokyo without a car, our guide to getting around Izu explains the Izuhakone Railway to Shuzenji and the buses over the Amagi Pass.
