[Maz1]

A normally health blackcurrant bush , has now developed a serious leaf problem.
The leaves are turning black in parts + the bush is looking very 'sad '. Never had this before .
Sorry can't add a photo .

Any help would be much appreciated.

Thanks .

[Gardener and Rabbit]

Aphids (greenfly/blackfly) can do this, and the stunted leaves on the ends can leave the whole bush looking very sad.  There are some pictures and advice on the RHS website if this looks like your problem:

https://www.rhs.org.uk/advice/profile?pid=889

G&R