Can we have some more information please - its quite difficult to give a useful answer without it. How long have you had the fuchsia? Is it in a pot or in the ground? In full sun or part shade? and anything else you can add that might be relevant, assuming you can't add a photo.

Was it newly planted last year? It might still be establishing a good root run, especially with this dreadful season we are having. You didn't put your county on your profile and knowing where in the country you live would make a difference. All except the very hardiest fail to survive the winter at all in my sisters garden in Ayrshire, whereas most of mine are growing well in mild West Wales.
Take heart, there is still time for it to take off, and nothing much you can do to encourage it apart from perhaps putting a cloche over it. (Never seen it done but you might want to try it.) Are you sure its is a hardy one?
Can you remember what variety it is?

Hi
Thanks so much for responses. I can't remember what variety it is. It was planted in a pot last year and survived quite well... I topped the pot up with fresh potting compost around April it has been in a partly shaded place but has plent of light.
I was wondering if it was maybe too wet we are in Manchester.
I have actually now transferred it to a small pot fed it and brought it in to the kitchen windowsill to keep it out of the wind and rain. All my others seem ok have moved them out of the rain as well though as it's been really wet here so they are getting plent of sun shade and shelter.

Part shade is fine - when you potted into a smaller pot, was that easily done, in other words, was the rootball small enough to go into a smaller pot? I was just wondering if it had been potbound, but obviously not if you got it into a smaller pot. Was it on its own in a very large pot previously?

Not much point in feeding it yet if you gave it some fresh compost - there is usually enough fertilizer in potting compost to last six weeks. More isn't always better.
Its been exceptionally wet here too and my established ones are all doing well so don't worry about the rain. Shelter from very strong winds is helpful though- the less hardy ones can suffer from leaf scorch if there are very strong cold winds.

It was in a fairy big pot on its own and very easily moved. It looks healthy enough just very small and it doesn't seem to be getting any bigger. As I say the others are all growing fine.

It might now do better in a smaller pot - plants in pots which are too big for them often don't do too well because there's a lot of potting soil around them that's unoccupied, and that can cause problems. That said, I've noticed that fuchsias in the ground have been slow to get going this year, likely because of the very dry weather back in April.