How to prune Black Currant Bush?

Hi all,

I am no gardener.
I have had two pot grown blackcurrant bushes for three years and we never seem to get much of a harvest, no doubt due to me.
I attach a couple of photos of the two bushes and would like some instruction as to how and where to prune.

Many thanks for any help.

 

The first thing I would suggest is that you grow them in the ground, not in pots. They can easily get to a couple of metres tall and quite wide. Imagine how much happier their roots would be in a less confined space.

OK, imagine they are in the soil. The next thing to do every November is to cut down one third of the stems to a strong outward facing bud near ground level. Then thin out any straggly shoots.

Their best fruit comes on growth made the previous year, though they do fruit on older wood, just not so well.

Give them a good feed in spring and away they will go.

 

Thanks for your reply, out of the pots they will come.

 

I've had 3 bushes for about 8 years now and they perform well.
Do you know what variety yours are?

As @Tidemark says, they'll not be happy in pots so great that you can get them in the ground. Most need about 6ft minimum between bushes as you need to get to them for picking.

Most blackcurrants will get to about 5-6ft tall and about 5ft wide such as my 2 Ben Conan.
The other bush I have is Ben Sarek which is much smaller. It only gets to about 4ft and about 3ft wide. It's the variety used for making Ribena as all the berries ripen at the same time so can be harvested in one go. The berries are also much larger than average.
This year I got 3.8Kg from the 2 Ben Conan and 2.5Kg from 1 Ben Sarek.
When it comes to harvesting, you can cut the entire stem with berries back to the ground and sit at your leisure and remove the strigs of berries, or as I do pick them in-situ, which is a long process.

Each year they send up multiple new stems from the ground.
So around now (when the leaves have fallen) I can see the Conans have about 40+ stems each.
I'll take out about 12-15 of the oldest stems. I cut the stems right back to the ground as low as possible and try not to leave any stub - otherwise you end up with a mass of dead stubs after a few years.
In Spring I give them a handful of Vitax Q4 each (which really does seem to improve quantity) and a mulch of rotted manure.

Birds love them and they're not easy bushes to cover, but.. if you can hang a few CDs in pairs somewhere where they can spin in the breeze somewhere near the bushes birds will not come near them. I use 2 pairs of CDs for the 3 blackcurrants.
Over the years I've found them to be the very best deterrent of all for birds.
But they must be hung by a single thread of string and not a loop of string, so that they can spin in any breeze. Hung in pairs, I guess other birds see them as huge flashing predatory eyes.
I use the CD method on raspberries (summer and autumn), blackcurrants, blueberries and blackberries - none are covered and the birds don't take any
Remove the CDs as soon as you've harvested so that birds will return.

 

And you can listen to them again.

 

Thanks again for more help, unfortunately I have no idea of their variety.

 

You will find that you can root cuttings easily; its a good use of the prunings, and could increase your stocks of either variety named above, if so desired.
I have in a previous year (2016 ??) bought 2 each of three 'Ben' varieties (from Lidl!), increased stocks by cuttings first year to 18, then when needing to move gardens, struck cuttings to have 15 from which to select 12 young bushes for the new plot. Now in their 3rd season. Great value from small outlay of 6@ £2.95 .....

 

WOW that's a lot of blackcurrant bushes!
Are you a blackcurrant jam-a-holic?

They also self seed as I often find young plants in the area around them.
3 bushes are quite enough for me, but I do really like them.

 

I also propagated all of my blackcurrant plants. They started as cuttings taken from a single plant of unknown variety back in 2015/16.

I grow them in 14L pots and provided that they are fed and sufficiently watered during the flowering/fruiting period, they crop very consistently year after year.

As the bushes are located in semi shade, next to a row of tree canopies, they don't respond the way I'd like to autumn pruning.

Typically, any maintenance cuts done to the bushes after the fruiting period in August will trigger new growth and even flowering which remains too tender to survive winter so I leave pruning till late winter or early spring the following year.

There are various ways to prune and train a blackcurrant. They can be made to adopt espalier fan shapes or freestanding single stem columnars or the multi stem bushes which I prefer.

When I prune, I aim for the stems or potential stems (ie buds) to form the outline of an upside down traffic cone. Knowing that the fruit will weigh the stems and branches down, I try to keep the stems to about 40deg max to the vertical.

I remove dead and dying stems/branches, remove crossing stems/branches, inward pointing and downward pointing branches and buds which I guesstimate will form branches in the wrong direction.

I leave a 5-10mm section above a bud or a young branch to account for dieback when pruning a stem.

When the stems become too old or the whole bush too unwieldy, I hard prune them to force new growth in the way I'd like.

This is exactly what I did in late March 2021:




And, in late June 2021:

 

I got one Big Ben plant last November for £6 reduced at a garden centre, planted it and planted up the cuttings from the initial prune and have six more plants to go in this winter if I want. Every cutting took which was nice. I'm going to try a couple as a fan along a fence I think.