There is one proven way to increase the yield of blackcurrant even if the berry has become small and has noticeably decreased.
The problem will have to be solved comprehensively.
First you will need a cuttageof the plant, and then add the necessary enrichment.
You need to start by examining the bush and, in addition to the branches affected by possible ailments, you need to select the thickest shoots and cut them to the ground.
The remaining shoots are cut to half their length.
In this case, the location of the kidneys should be controlled and retreat from them 2-3 centimeters.
You also need to remove those branches that lay on the ground - they will simply interfere.
Shoots that have grown in the past or this year, it is better not to touch.
Aftercuttage, you can start earthworks.
First you need to loosen the soil around the bush to a depth of 5-6 centimeters.
Then add compost and mix it into the soil.
In the final, use mineral fertilizers at the rate of 25 grams per 10 liters of water.
The result will be noticeable already next summer!