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Pruning guide · Fruit tree
Olive tree: when and how to prune
Olea europaea
Prune an olive tree in spring, in April–May, once the frosts are over: keep the crown open and remove inward-growing branches and water shoots.
An olive tree grows slowly, regrows readily, even from old wood, and takes pruning well. Here the difficulty is not the pruning but the frost: that is why you only prune once winter is really over, and never in autumn. It flowers on last year’s wood, so light, regular pruning gives more flowers than a hard prune every few years.
| Pruning months | April–May |
|---|---|
| Nesting season (15 March–15 August) | Take care in April–May |
| Flowering | June |
| Good for bees, butterflies and birds | Little |
| Native to Belgium | No, planted |
Olive tree: when to prune it?
Prune in April–May, once there are no more hard night frosts. The wounds then close quickly, and the new shoots have all summer to harden off.
After a hard winter, wait until the tree starts into growth: you can then see which twigs are dead. Only then cut them back to healthy wood.
Don’t prune in autumn or winter: wounds and young shoots are then vulnerable to frost. Prune a potted tree that overwinters indoors only once it is back outside.
Olive tree: how to prune it?
- Use sharp secateurs for thin twigs and a pruning saw for thicker branches, and cut just outside the branch collar, without leaving a stub.
- First remove dead, diseased and damaged twigs, and branches that cross or grow inwards.
- Cut out the water shoots: the upright, fast-growing shoots on thick branches and on the trunk, and the suckers at the base.
- Keep the crown open so light and air reach the centre. An old rule of thumb from the south: a bird should be able to fly through it.
- Trim a potted ball-shaped olive lightly: shorten last year’s shoots by a third at most, so it stays compact and still flowers.
- An overgrown or bare tree can be cut back hard, right into the old wood: it will regrow, but flower less for a year.
How much to cut, and how often?
- One prune a year, in spring. Better a little every year than a lot every few years: that leaves enough young wood to flower.
- Remove no more than a quarter to a third of the crown at a time, unless you are deliberately rejuvenating an overgrown or bare tree.
- Prune a tree that suffered frost damage in winter only back to healthy wood, and no further: it needs its leaves to recover.
What does it mean for wildlife?
- An olive tree in the open ground may hold a blackbird’s or chaffinch’s nest in spring. The April–May prune falls in the nesting season (15 March–15 August): check the crown carefully first, as disturbing an active nest is against the law.
- The small creamy-white flowers in June are mainly wind-pollinated: bees find a little pollen at most. Plant lavender, rosemary, thyme or oregano around it: they suit it and are full of bees and butterflies in summer.
- An olive needs no poison: brush off scale insects, and ladybirds, lacewings and parasitic wasps will do the rest.
- The grey-green prunings look lovely in a vase or a wreath; the rest can go on a dead hedge, shelter for hedgehogs and insects.
Common mistakes
- Pruning in autumn, so the wounds and young shoots freeze in winter.
- Cutting back a frost-damaged tree as early as March, before you can see what is still alive.
- Letting the crown grow dense, so the leaves inside drop and diseases such as peacock spot have free rein.
- Clipping a potted olive into a tight ball every year, so it hardly flowers any more.
Caution: Tolerates a few degrees of frost, but not wet soil: make sure drainage is good, and protect it in hard frost.
Nearby: related pruning guides
Similar to: Difference from oleaster
Plant profile: Olive tree · Pruning calendar and basic rules