William. Lotus root (renkon, 蓮根) is a Japanese delicacy, particularly when it’s spiced with a piquant mustard-type filling, when it’s then called “karashirenkon” (辛子蓮根).. Some 90% of Japanese renkon are grown in Kumamoto due to the fortuitous combination of flat land and abundant water. Ironically, the abundance of water has proven too abundant this year, and renkon farmers are worried that they will not be able to get their crop in. There is a shop on the Kokai shopping street that specializes in renkon which I highly recommend. https://kumanichi.com/articles/361408