The seed require a 2-3 month storage at 40F then lightly cover the seed soil temp 65-70F
Could try the seed trading/exchange forum to get some seed

I know one thing about hydrangeas! And that is I have found it completely impossible to clone one. There is this magnificent (lesser known breed) specimen at a bus stop in Mansfield ct that I have been tiring to root for YEARS with zero success. I can make them live a long time but they never ever ever root.

The mom plant is HUGE! Maybe a hundred years old. It resembles more a tree than a bush or shrub.

I will keep tiring though. One of these days.

Good luck with the seeds.

I have hydrangea seed, I think. I have collected some but am having a difficult time with seed identification, cant find it on seed site. I may just have a bag full of chaff, but have ws'd some.

Thanks for the growing info. I'll try starting mine out at the unheated basement window, then move them up under the lights. Maybe I planted chaff too - it was hard to tell. Are the seeds very big?