looks like Hydrangea aspera. Although it looks very healthy tt looks over crowded it is usual in spring to remove a quarter to a third of the shoots to the base of the plant?

It looks more like a lacecap form of H. macrophylla to me, Drc. Lornachan, lacecap Hydrangeas are the original form of Hydrangea. The little flowers in the center that barely open are the fertile flowers, and they produce the pollen and the seed. The big flowers around the edge of the cluster are the sterile flowers, and all that they do is wave at the butterflies as they go by. It's only in the past 100 years or so that forms with all sterile blooms have taken over the market, and lacecaps are still sold for their delicate grace, and ease of bloom.

While the leaves look like my H. macrophylla the flowers dont Tugb?

This is what's known as a lacecap hydrangea, as Tugbrethil suggests - there are three flower forms in the Genus of hydrangea - conical, mophead and lacecap, and the lacecap group is the largest. Personally, I prefer them to ghastly mopheads, but that's my personal choice - if you want a mophead, that's what you need to buy instead, so look in the Hortensia group for those.

thanks for that but where does the Hydrangea aspera come then?

One of the lacecaps

Drc - there are several species of hydrangeas; H. aspera is one of these and H. macrophylla is another. The lacecaps and mopheads are all forms of the latter. H. aspera is a bigger shrub, flowers later and comes from a different part of Asia

And has flowers which resemble lace cap in structure.

Thanks everyone

Thanks Andrew and Bamboo, got it now.