[Lastcast]

Hi, noticed that we have some purple/red patches on the leaves of one of our Blackcurrant bushes, (attatched pic) any suggestions as to what it could be. Can be apply anything to eliminate it ? Thought it may be a insect but unable to see anything on the underneath of the leaves. The bush is 3 years old & it had a mulch of compost & well rotted manure applied over winter.

[Yorkie]

Looks like classic blackcurrant leaf spot to me.

The RHS page says there's no chemical control available.

Plant hygiene is vital.

[tangojulie]

It could be currant blister aphid.

http://apps.rhs.org.uk/advicesearch/Profile.aspx?pid=491

It is unsightly but doesn't hugely affect the crop. You can spray in the winter to destroy any overwintering bugs.

We hasd a bad infestation last year but spraying has cleared it completely this year.

[Yorkie]

You might be right there tangojulie 

[Lastcast]

Thanks for the replies, winter wash it is then !! I've now added the RHS website to my favourites.

[sunshineband]

 I am assuming you will pick off the affected leaves and destroy them, to reduce the number of bugs available to reinfect next season... as well as the einter wash of course