How do I prune a blackcurrant bush?

Blackcurrants are a stooled bush, meaning they are grown to renew themselves continually from the base rather than to keep a permanent framework. Wood grown last summer carries the best crop, two-year wood carries a fair one, and three-year-old and older wood carries very little while shading the middle. So the whole method is: identify the oldest, take it out at the bottom, leave the rest alone.

What you'll need

• Loppers
• Secateurs
• A pruning saw for old bushes (optional)
• Well-rotted manure for mulching (optional)

Step by step

1. Prune in winter, between leaf fall and bud break.November to February. The structure is visible and the bush is dormant. Some growers prune immediately after picking instead, which also works and lets you cut whole fruited branches into a bucket to strip in comfort.
2. Learn to read the wood by colour and thickness.One-year wood is pale, slim and unbranched. Two-year wood is darker and starting to branch. Three-year and older wood is dark, thick, twiggy and visibly less productive.
3. Take out about a third of the stems, at ground level.Choose the oldest and darkest. Cut as low as you can get the loppers or saw — right at the base, leaving no stub. Shortening them instead achieves nothing.
4. Remove anything lying on the ground or crossing the middle.Low branches drop their fruit into the soil where it rots, and congested centres keep the bush damp.
5. Leave the young pale stems entirely alone.They carry next summer's crop. Do not tip them, do not shorten them, do not tidy them.
6. On a newly planted bush, cut everything back hard.All stems to about 5cm above the ground after planting, and expect no crop the first summer. It builds a strong stool and it is worth the year.
7. Renovate an old neglected bush over two winters.Take out half the old wood the first winter and the rest the next, or cut the whole thing to the ground in one go and lose two years' fruit. The staged approach is usually better.
8. Feed and mulch after pruning.Blackcurrants are among the hungriest soft fruit. A nitrogen-containing general fertiliser plus potash in late winter, then a thick mulch of well-rotted manure around but not over the crown.
9. Check for big bud while you prune.Winter is the only time you can see the swollen round buds that mean blackcurrant gall mite. Pick them off as you go, or remove badly affected stems.

Tips

• The difference between blackcurrants and redcurrants is the single most useful thing to know in the soft fruit garden: blackcurrants are renewed from the base, redcurrants and gooseberries are spur-pruned on a permanent framework.
• A blackcurrant bush that has never been pruned will still fruit, badly, in a ring around the outside. Renewal pruning brings the crop back into the whole bush.
• Modern varieties such as Ben Connan, Ben Sarek and Ben Hope are compact, high-yielding and mildew-resistant, and Ben Sarek suits a small garden or a large pot.
• Prunings from a healthy bush root very easily as hardwood cuttings — 20cm lengths of one-year wood pushed two-thirds into the ground in winter.

Common mistakes

• Shortening all the stems to tidy the bush — It removes the young wood carrying next year's fruit and leaves the old unproductive wood in place — the exact opposite of what is needed.
• Pruning blackcurrants like redcurrants — Redcurrants and gooseberries fruit on spurs on old wood and are pruned to a framework. Applying that method to a blackcurrant removes the crop.
• Leaving stubs when removing old stems — They die back, rot and provide nothing. Cut right down at the base.
• Letting a bush go unpruned for years — It becomes a mass of old dark wood with a thin fringe of fruit around the outside and very little in the middle.

Questions people ask