Japanese Yam

やまのいも

Hokkaido and Aomori Prefecture are the main growing regions, centered on nagaimo production. Grated yam ('tororo') is essential for wheat-tororo rice, as a binder in soba noodles, and in okonomiyaki batter. Contains abundant digestive enzymes (amylase) and a distinctive sticky texture. Traditionally nicknamed 'the eel of the mountains'

Taste & Texture

Grating produces a thick, viscous texture. Nagaimo has a relatively mild flavor while jinenjo is rich and full-bodied. One of the few types of yam that can be eaten raw

Season

MONTHLY AVAILABILITY

Jan - Dec

PEAK

※ Season is based on domestic field-grown availability

How to Choose

  • For nagaimo, choose smooth-skinned roots with no blemishes and uniform thickness; cut surfaces should be white and fresh-looking.

  • For yamato-imo and jinenjo, select round, heavy roots.

  • For all types, avoid cracks or discoloration.

How to Store

  • Store uncut yam wrapped in newspaper in a cool dark place or refrigerator vegetable compartment.

  • Cover cut surfaces with plastic wrap to prevent oxidation.

  • Grated yam can be wrapped and frozen.

Shelf life Refrigerated: 2-3 weeks; grated and frozen: 1 month

Nutrition Facts

Wholesale Market Data

MARKET INSIGHTS

CHEAPEST Jan ¥356/kg
BUSIEST Dec 5,979t
Volume (t)
In season
Price (yen/kg)

Source: MAFF Wholesale Market Survey for Fresh Produce (2023)

Production Ranking

100% Domestic
Hokkaido52.5%
Aomori32.0%
Nagano4.1%
Chiba3.5%
Gunma2.5%
Others5.4%
10%+
5%+
2%+
0.1%+
None

Map data: National Land Numerical Information (MLIT Japan)

#
Prefecture
Harvest (t)
Share
1
80,800
52.5%
2
49,200
32.0%
3
6,340
4.1%
4
5,360
3.5%
5
3,890
2.5%

Source: MAFF Crop Statistics / Agricultural Census (2023)

Top 5 Prefecture Harvest Trends (2018-2023)

Hokkaido
Aomori
Nagano
Chiba
Gunma