Sulking fruit bushes

I am trying to work out what my fruit bushes are deficient in. They were 3-4 year old bare rooted plants, planted last winter with fungus and plenty of well rotted manure. They have had one dose of chicken pellets this year but to be honest that's about it. I originally thought it was not enough sun and was going to move them (sun from midday) but after doing some reading I don't think that's it. Also, I have noticed that it is the bushes that have fruited a bit this year that seem worst affected (so have obviously used up something). The bushes I had non fruit on are dark green and healthy looking.

My currant:



And one of my gooseberries  (2 varieties out of 3 are like it)



My soil is acidic if that helps

Best go and buy some more chicken pellets then! The rain water washing nutrients out would make sense...

I am just in the process of doing the weeding Nobbie. I was on honeymoon for 3 weeks and they grew like crazy so it is only a months worth of weeds (honest!). I will see what I can do about getting more compost down to the plot - it is difficult as we don't have any vehicle access to the site at all and my home made stuff is now here near ready!

Is there an organic alternative to sulphate of potash do you know? I will do some googling anyway. Thanks for the tip