A mid-summer or late-summer blooming hydrangea paniculata? Go to the link below and compare your blooms to the pictures in the plant nursery's website to get variety names:

http://www.hydrangeasplus.com/category-s/111.htm

It reminded me of some Quickfire/Little Quickfire blooms but QFs are normally early bloomers and I would have thought their blooms would be more pinkish now,.. in most places.

How old is the plant, do you know? What are its approximate dimensions?

Take cuttings and start more plants.

I’m thinking maybe a Pinky Winky with the cone shape...it can get to 9’/10’