Japan Flora: Stems to more than 1 m. high, much branched, 4-angled; leaves lan­ceolate, 7-12 cm. long, 1-3 cm. wide, rounded and clasping at base,  scarious; spikes many, in terminal corymbs, densely many-flowered; flowers small, blue-purple, about 1 cm. long, exserted from the bracts.

Sometimes cultivated and natu­ralized in the western part of Honshu and Kyushu.  In­troduced from S. America.