Hi Karen, I know this one as Duranta "geisha girl" I have one by my back door, it attracts butterflies and the honeyeaters.
It's a bushy shrub that will grow to about 6 ft. I keep mine pruned because it does sprawl a bit and hangs over my driveway. Pruning after flowering will keep it shrubby. Otherwise it'll get all leggy.
It has golden yellow berries after flowering and sometimes it's still flowering at the same time and looks really nice with the colour contrast.

You can also grow it from cutting. Not easily but you can do it. Take a few bits at odd times throughout the year and stick them in the ground, If it doesn't work keep trying.. Heat may work I haven't tried that.
I have photo's but don't have time to post them now. They're on my laptop and I'm on the main computer and dashing off to work in a couple of minutes..

I love how you've planted yours...
and sounds as though you have the perfect spot for your hydrangeas now...

Have to run.
Pauline