This long-leaved plant was being grown in Kanazawa-shi in Ishikawa-ken and its leaves are used in tempura and to make some reddish drink. My mother saw it on the program via her satellite dish here in the US on Friday, January 6th. She says it was called 'kinjiso' but I can't find it on Google. The leaves were long & narrow, green on the top part and reddish on the underside. The farmer brought in samples to the show. I thought it might be shiso until she mentioned the long narrow leaves.
I've checked the show's web site but it skipped mentioning this show, it talked about a past one on kamaboko and then future programs on strawberries and something else.
If anyone saw the program and can give me more information about the mystery plant, (including its flavor!) I'd appreciate it. She is interested in adding it to her vegetable garden.