This small size, green colored hosta is a non-registered cultivar which is a form of H. longissima found in Japan. Flowers are medium purple in color and are borne from mid-September to October.

Mikiko Lockwood in an article on The Hosta Library titled, A Little About Japanese Hosta Terms defines the term mizu as water, 'Mizu Gibōshi' or H. longissima and the term shirobana as white flower.