They can get big so don't do what i did and plant them close to the house. I didn't know they got so big since I had never seen one bigger them 6ft. Then I ran across some beach side that were 20ft and just as wide.

I have never seen them get that big...maybe 8 feet tall. How thick was the main stalk to support such weight?

Mine get 12ft or usually higher in a growing season (March through mid December typically before it freezes) and I have to cut them back to get them into the greenhouse in the winter. They can get 7ft wide or more here if the branches spread a lot. I bet in your zone they would be really big. You can trim them to your liking. I would leave at least 8 to 10 feet between the trees unless you want to trim them every year. This year I tried to leave a lot on mine because 4 of them have seed pods.

Oh yes, give them room. They are trees! I have seen trees so wide, I could play ring around the Rosie around them. It does depend on the varieties...personally I only do dwarf trees now

Pea I would say the trunk was about 10"across on the first one I saw. After that a started looking around when I'm driving and I've found at least a dozen that size and ask a owner of one how old it was and she told me 39 years. It was in bloom. So pretty. All white blooms. She gave me two cuttings that I planted in my yard. There still small. And haven't bloomed yet. But my older one is about to I'll post pics when it does.