Taisho Nagaimo is a locally grown variety of Japanese mountain yam cultivated in the Tokachi region of Hokkaido. Grown in fertile soil and nurtured by the area’s significant differences between daytime and nighttime temperatures, it is prized for its gentle natural sweetness and exceptionally strong stickiness.
The Tokachi region experiences significant temperature differences between day and night even during the main growing period from July to September. During the day, the plants absorb abundant sunlight and nutrients from the fertile Tokachi Plain.
When temperatures fall at night, these accumulated nutrients are directed toward the developing mountain yams underground. This cycle is repeated throughout the growing season, helping produce Taisho Nagaimo with its characteristic firm texture, pronounced stickiness, and subtle sweetness.
The history of Taisho Nagaimo as a regional agricultural product spans approximately 35 years. Cultivation began with just three producers. Today, approximately 76 producers grow the crop across around 200 hectares of farmland.
Local growers work together to maintain strict cultivation and quality-control practices. Their efforts have helped establish Taisho Nagaimo as a distinctive agricultural product from Tokachi.
Taisho Nagaimo is shipped not only throughout Japan but also exported to international markets, including Taiwan and the United States.
Its naturally strong stickiness and mild sweetness make it an appealing ingredient for experiencing the distinctive textures of Japanese cuisine. For visitors exploring Tokachi, Taisho Nagaimo offers a delicious example of how Hokkaido’s fertile farmland and cool climate shape the character of local produce.