blackcurrants and redcurrants - leaves have holes everywhere

I think its about time I really try to help my pathetic blackcurrant and redcurrant plants. Hopefully with your advice i can do this. I will try to post a picture tomorrow but will start by describing the symptoms:

-every leaf is pitted with many small holes about half a centimeter across.
-Yield this year has been extremely low. about 10 berries per plant.
-Very little new growth.
-I havent seen any bugs with the naked eye so its either not a bug or they are bloody tiny.

They are sheltered by a brick wall and recieve a mix of full sun and shade through the day. They are a few meters away from a lime tree and a sicamore tree but are not shaded by them. The soil is fairly decent, ph 6- 6.5, and the blackberries, loganberries, rasberries next to them are mostly thriving. Fed regularly with phostrogen.

Thanks for any advice you can give.

Mark

 

Mark

For widespread leaf damage to fruit bushes, the first culprits that come to mind are sawflies. But they tend to leave the leaf veins. And you can often see the little so-and-sos at work if you look closely enough. Have you sprayed the bushes with any insecticide yet?