They prefer shade and tend to look terrible in full shade. They look best in dampish north facing/semi shade. Mine are doing well and same with any I have seen (not in full sun!)

Mine to looks stunning ,last yr it was a bit sad looking .

Its been in the garden 23yrs .

Last yr I gave it a good prune and its now looking great.

I live in West London, and I can't say I've noticed a problem with them - in fact, I passed a huge one in full flower the other day, and it looked absolutely fantastic.

Thanks for your suggestions - mine is in the shade and has been in the garden probably about 18-20 years I think so perhaps it needs a prune

And give it a good feed as well

Thanks everyone

Will any plant feed like be ok or does it have to be special like roses

Use something general purpose, such as Growmore, or Miracle Gro multi purpose.

I took the plunge and gently pruned my Mahonia a few weeks ago and gave it a good feed - cant believe how it has been transformed - good growth and looking very healthy already - thanks for all your suggestions