HYDRANGEA

Yes. Chop off the dead flower heads first to give yourself a good view of what you are doing. Look for healthy pairs of buds quite low down (1'- 2' off the ground if you are brave enough)! and cut back to above them. Then give it a feed of blood, fish and bone.

thank you so much for your advice really helpful!!

I also find a mulch of garden compost beneficial to keep the roots cool and moist, just in case we get a hot, dry summer

You are being hopeful, Andrew!!! Great to be so optimistic. :-)