I've got a big fat hydrangea, what do I need to do with it?

[Annianni]

Our lovely new house has an enormous hydrangea in the front garden, and it's looking a bit tired now.

What do we need to do?
Does it need pruning back?

Tia

[Bienchen]

If it is a mophead hydrangea you should do nothing now and after last frosts cut off a third of the stems at the base and remove the faded flower heads from the rest. If you cut off the flowers now, they are more likely to produce new growth which will be killed by winter frost. The old flowerheads protect the buds for next summers flowers.

[Annianni]

Thanks, that's great.

[ClareMarriott]

Also if the flowers are pink, you have an alkaline soil and if they are blue, then you have an acid soil

[redadmiralsinthegarden]

and if you keep the old flowers on over winter they provide hibernation for ladybirds and other insects.