yes you can.
I always hack it down hard in February and leave it all to its glory through the summer.

this flower is so common im starting to get sick of seeing it but never the less it is a bueatiful flower.

I do the same as Sbg ... it's a very resilient shrub! Common it may be, very pretty flowers though.

Wildlifebalcony I wonder if you are confusing it with the rose of Sharon hypericum which is a low grower? I can't imagine getting sick of Hypericum Hidcote but i guess it takes all sorts.

Thank you all for your imput.
Do I have to wait until Feb,it it is so big that it needs to be cut down a bit,will it do any harm to prune after this lot of flowers die off???

yes you can cut it down after flowering.

It has just finished flowering,can prune it now ,before the weather begins to get cold?

Yes. Where I used to work there was a border of them and they were cut down every winter to about three feet.

thank you very much for your reply.

Steragram..when you say "winter" when do you mean exactly?I really need to cut mine down but do not want to spoil it by letting frost get to it.Thanks

I used to work at Malbank School in Nantwich and I seem to remember they did theirs quite early in the autumn term. If you do it now and we have a really mild autumn so that it grows a few new shoots the only frost danger would be to those shoots, no harm would come to the mature wood. But all things being equal I'd prefer to wait until perhaps November.

Thank You Steragram..Yes,November would be better as it is still flowering and should have finished by then.More about pruning...I have a Red Robin and a Mock Orange which also needs cutting right down(see Pic,the 3 bushes are together)..what about these .when can they be done?
Also my Californian Lilac is on it`s way to being a tree!!!(see pic)...but is sort of flattish and widespread on a single trunk...what can I do about this...you cannot see in the pic but it is very dense at the top.
I know the garden has been neglected but have not been able to do it this year due to being away a lot and at the wrong time of the year ,if you understand me.

Lot to catch up with.

The mock orange needs pruning immediately after flowering. If you do it now you will lose next years flowers. All the shrubs in your border will want to get bigger than they are at present.

My Californian lilac is also flattish on top and on a single trunk but it is about five feet tall and very wide.(It must be getting on for 20 years old) All I do to it is occasionally cut off any growth that hangs over the path. once I cut off a big branch - people said it would not regenerate but it is doing, in a half hearted sort of way. I think you might need to decide whether you want a shrub hedge, in which case you'll have to prune everything, or whether to thin things out and let some of them develop their natural shapes.

Sorry I have no experience with Red Robin so I looked it up for you. Late March-early April is apparently the best time, to encourage the new red growth.

Thank you very much for your advice.I think I shall do away with the mock orange as the Californian Lilac is next to it and is taken it over.
T