Mock orange with hardly any flowers

Hi all.

I have no doubt this is my fault. I have a mixed hedge, with mock orange in it. It's well established and seems healthy enough, but I hardly get any flowers on it.

This could be down to my pruning regime. I simply take the electric hedge trimmer to it whenever I think it needs a haircut.

Is there a proper way?

 

Prune after flowering then leave it be until it has bloomed the following year!