This cultivar of unidentified parentage and and unknown originator in Japan was registered by Peter Ruh of Ohio in 2002 and re-registered with new data in 2018. It is a miniature size (3.5 inches high by 7 inches wide) hosta with light green foliage. The leaves are lanceolate, moderately wavy and slightly shiny on top and bottom. Lavender flowers with white edges bloom in September on scapes about 9 inches tall followed by viable seeds.

The registration materials state: "...dwarf size; rounded clump"

According to The Hostapedia by Mark Zilis (2009), "One of the smallest hosta cultivars, 'Ko Mame' makes a neat, low mound of foliage that can be useful in the shaded rock garden."

This cultivar was originally (2002) registered with Kenji Watanabe of Japan as the originator but that was changed in the 2018 re-registration to Originator Unknown.