That looks like it might a lacecap H.macrophylla which means there's no easy answer. If you prune these back (in spring, not in autumn) they don't flower - you can selectively prune out some stems in spring, but that means the remainder will get longer and produce larger flowers. The only attempt at controlling its spread you could make is to prune it all back by two thirds, in late spring, when the weather is warm and there's no risk of frost,followed by some balanced fertilizer. You won't get any flowers that year, but hopefully you will the following year.

thanks Bamboo, will give it a go in March/April :O)

Best wait till mid to end of May instead...

thank you :O)