Blackcurrant: when and how to prune

Blackcurrant: when to prune it?

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Straight after picking, in August, is a handy time: you can see clearly which stems have fruited and which are young and vigorous. If you like, cut the old stems off with the last strings of berries still on them.

If you prefer to prune in winter, do it in November–February, when the bush is bare, in mild weather and not when it is freezing. You will also spot the swollen, round buds of big bud mite: pick them off straight away.

Don’t prune in spring or early summer: the bush is already flowering in April, and in June–July the berries hang on the stems you would be cutting off.

What else to prune in those months? January · February · August · November · December

Blackcurrant: how to prune it?

1. A blackcurrant grows as a stool of stems from the ground, without a leg. In the winter after planting, cut a new bush back to a few buds above the ground: plenty of strong shoots will then come from the base.
2. Learn to recognise the old stems: they are dark, thick and much branched. Young stems are light brown, smooth and straight.
3. Every year, saw or cut out about a third of the stems, the oldest ones, as close to the ground as you can. Don’t leave stubs: they only produce weak little shoots.
4. Keep the strongest young shoots from the base and don’t shorten them: next year’s crop hangs on that one-year-old wood.
5. Also remove weak, diseased and sprawling stems, and stems hanging so low that the berries touch the soil. The bush then gets light and air, and less mildew.
6. Rejuvenate a neglected bush full of old wood over two winters: each year, take half the old stems out at the base.

How much to cut, and how often?

• About a third of the stems every year, the oldest: that way no stem is older than three or four years and the bush keeps renewing itself.
• A mature bush has around ten stems of different ages; remove surplus weak young shoots.
• Don’t prune it like a redcurrant, with short spurs on a permanent framework: shortening every stem cuts away the young wood along with the crop.

What does it mean for wildlife?

• In April the blackcurrant bears small greenish-red flowers: an early source of nectar and pollen for queen bumblebees and solitary bees. The more pollinators, the better filled the strings of berries.
• Blackbirds, thrushes and blackcaps love the ripe berries: put a fine, taut net over what you want to pick yourself, and leave them the rest.
• Pruning after picking in August still falls in the nesting season (15 March–15 August): blackbirds and whitethroats sometimes raise a late brood in a dense currant bush. Look first, as disturbing an active nest is against the law. Winter pruning falls outside it.
• The leaves feed the caterpillars of the comma butterfly and the magpie moth. So don’t spray poison against aphids: ladybirds and tits will deal with them.

Common mistakes

• Pruning it like a redcurrant, shortening every stem, so the young fruiting wood is gone.
• Never removing old stems, so the bush fills up with old wood and bears fewer and fewer berries.
• Cutting old stems halfway down instead of at the base, so a broom of weak shoots appears.
• Leaving the fat, round buds of big bud mite in place, so the mite spreads.
• Pruning in August without checking for nests first.

Nearby: related pruning guides

• Redcurrant
• Gooseberry
• Jostaberry
• Raspberry
• Blueberry

Similar to: Difference from redcurrant · Difference from jostaberry · Difference from flowering currant

Plant profile: Blackcurrant · Pruning calendar and basic rules