I am also looking for this bush. I have read that you can dig up the suckers from the base and they usually have a few roots to get it to grow more and get a new bush.

I would definitely be willing to try rooting if you would be willing to give me some cuttings. I created my trade list. Also I saw you are looking for day lilies, my mom has a million, mixed variety she is always thinning out.

From what I read the best method is the "tooth pick" method. You have to do it in August and let it scar over, then cut from the bush and put in rooting bed. I thought I would try to root some this summer and see how it goes. My bush doesn't have any suckers yet. It is about 4 years old.

There is a large bush with yellow flowers at the arboretum on my campus. I got permission to dig up one of the sucker so I'll let you all know how it goes.

Chris--Message me. It is in the upper R corner of my page.