The Hosta Library (hostalibrary.org) includes a database that is supervised by its owner,  Hugo Phillips. It includes registration details from various growers, collectors and hybridizers. Apparently, Louisa, a sieboldii hybrid,  was first discovered in 1946 but it wasn’t named until 1969 and then was registered in 1986 by Frances Williams and Connie Williams. That’s a long time for hosta folks to be looking at such a small hosta. Narrow green leaves with a white edge and white flowers keep it simple. It is a vigorous little hosta and grows well as a groundcover. We have some growing on the left of the entrance to our hosta display garden/left of under the overhead sign. We always pot some up each year and they always leave before the summer is out.