ES, P.P. 15298, is still protected by patents. I would try propagating another variety of hydrangea.

I rooted my dark pink no name that way and noticed noticed nothing is happing yet root wise so I think mayby they need just a little more active growth time before they are ready to root. My ES has rooted on its own it a few places where the branchs touch the ground but they have been on the gound since I mulched last may.

I had no luck your way either. I had great luck using the cuttings method. Take a young shoot about 6 inches long or so, rooting hormone on the end, stick in loose soil with lots of perlite, maybe solid perlite would work too, keep covered with plastic. I can't remember how long it took but it was only a month or so. Gradually uncover it and harden off after it's rooted well. I did three that way. I did 2 blues and a variagated leaf. Don't know the names of them as they belonged to my neighbor. I overwintered mine for the first year but in your zone you probably wouldn't need to, just give good winter protection the first winter it's in the ground.

Do you think it is too late in the season to take cuttings and keep them indoors? I could either keep them in a sunny window in my basement, or in my attached but not heated garage. My concern is that the plant is at the end of it's growing cycle and trying to shut down for the season, not create another one of itself!

Any feedback is appreciated,
TulipSmiles

I took cuttings from a storm damaged plant about this time last year and propogated them in side the house in front of a window. Suprising everyone of them took. Was a pain to remember to water them all winter though. I kept a tray with water under them, and misted them on top. Some dropped their leaves but put them back on a month or so later. My es rooted itself where it was weighed to the ground with multch.