Virginia Sweetspire (Itea virginica 'Henry's Garnet')

I found this on a clearance rack a couple years ago. It has put on some growth and I went to trimming it and now it's limbed up, I'd say about 2 ft tall, it was just small when I planted it so hasn't grown that much.
I'm wondering if I can grow it up as a tree, and it says 6 ft all and wide on the tag but thinking if I go to limbing it regular it may get taller? Maybe I need a different variety altogether? Not wanting anything much bigger than 8x8ish or so anyway.
Thoughts please?!