There is an image of this
cultivar on the
Hosta Library. From the photo on the HL website, it appears to be a small
size hosta with light green leaves and a misting of
creamy white specks. This non-registered cultivar was
originated in Japan.
W. George Schmid (1991) describes a Rasha leaf as one that
is a "Uniquely contorted leaf with an unevenly knotty
and knurled surface texture".
Mikiko Lockwood in an article on The Hosta Library titled,
A Little About Japanese Hosta Terms defines the term iwa as rock, Iwa Gibōshi or