can anyone tell me what this plant is?

It looks as if it might be a Corkscrew Willow, judging by the curly leaves, but do the stems also rwist? If not it may still be a Willow, but which?

Yes, I'd agree - there's a slight doubt in my mind as to whether it's a Contorted Willow (Salix babylonica tortuosa) as I can't see any twisted stems. Definitely a Willow, though!

Thanks for your replies, yes the stems twist as well, I have googled it now and got some picks up of corkscrew willows and that's def what it is, so thank you mystery solved.

Make sure you clip bits off, not only to keep it in the shape you want, but also because if you don't, it can grow into quite a large tree!

willow tree roots can do some damage to your drains, they go to water. Have been known to get into pluming and cause headaches.