A well managed blackcurrant bush can provide quite a harvest in a year with more than enough to meet the need of the kitchen and very often surplus to freeze for the winter months. If left to their own devices though they get overcrowded, begin to crop poorly and become prone to viral diseases and gall mite.
Some people ‘prune’ out the heavy fruiting branches during the summer prior to picking as it can make harvesting easier but this can result in the wrong branches being removed. Instead I find winter pruning is better as it helps maintain the vigour of the plant and means the plant remains a productive part of the fruit garden for much longer. Aside from it being a handy winter garden task when the rest of the vegetable garden has slowed down, the leaf drop means it’s easier to see the overall structure of the bush.
The objective of winter pruning of blackcurrants is to try and create a light airy upright habit and shape with as much of the last seasons new growth available (as these will be the main fruit bearing branches in the new season). To do this you will need to carefully select and remove the branches that are causing congestion at the base of the plant and those that are cluttering up the upper levels of the plant.
An hours clever and careful winter pruning of a neglected blackcurrant bush can be very successful, and whilst the pruning required may initially reduce the crop in the following season, in future years it will pay you back in spades, or should that be crumbles, ice-creams and jams.
What You Will Need
- Lopers or a small pruning saw
Look closely at the unpruned bush. Try to pick out the crowded or stagnant areas and look for the main growth and stems that will contribute to a bowl structure, also identify those that cause poor air circulation.
Familiarise yourself with the different types of growth. The new shoots (which will fruit next year) will have smooth bark the colour of strong tea. Second year growth will have already have fruited in the last season. The bark will be a rough grey colour and it may carry a loose bunch, or strig, of fruit stems.
The bark of third year growth is black and rough to the touch. These will not have borne fruit in the last season but many will be carrying the important second and first year growth.
Start pruning by cutting out the weak and congested whips from the centre of the shrub. Whilst these could bear fruit in the coming season the crop will be poor and their growth will reduce air circulation and promote disease. Also remove and burn any diseased branches.
Identify the third year growth that is either unproductive (ie not carrying a good crop of second & first growth) or doesn’t contribute to the overall upright habit and shape of the bush. Lop this out as close to the ground as possible.
Remove any branches that cross over and are rubbing. These run the risk of damaging the bark and encouraging disease
Prune out any second year growth that either is not supporting good first year growth or is not adding to the overall shape of the bush
Finally scatter some good organic granular fertilizer around the base of the plant and then mulch it with some good quality homemade compost.