All hosta species are edible but H. montana and H. sieboldii are most popularly used for vegetables. H. plantaginea is grown for its sweet flowers. In Japan the species H. montana is also known as oobagiboushi. Ooba means large leaf and giboushi means a type of cylindrical column or ornament used on Japanese bridges.H. montana is found growing wild in the mountains and is also cultivated for the vegetable market. Urui is the word used to describe the young leaves of this particular species.

Taken from this blog :http://rawedibleplants.blogspot.com/2014/06/hosta-species.html