Like Frank, I planted in Spring 2019. I was not expecting much, but it had several blooms and even reached its expected height. I was very pleased with it to be planted such a short time.
DWG is one of my many favorites. Does very well in my zone 5a. Never measured to check if it reaches the registered height and bloom size but I can tell you that it surely impresses me.
I don't recall getting seeds from it. I'll have to try this summer. Can't imagine why I never tried before. There is a very pretty "child" in the data base.