If your garden’s in danger of being overgrown by shrubs, bushes, hedges or trees, then it’s time to do something about it.
When should I prune?
The best time is just after your shrub or bush has finished flowering, or (if it flowers in autumn or early winter) at the end of winter—before the sap starts to rise. (If you’re in the Southern Hemisphere, then come back in six months’ time; if you’re in the tropics, then winter doesn’t come into it.)
How much should I prune?
That’s a vexed question for most people, who are understandably scared that they’ll kill their favourite bushes. “Be bold!” is the answer. Cut back by half in the first year, and by a third in subsequent years, until your bush or shrub reaches the height you’re after.
By pruning hard, you’re encouraging thicker, denser growth—so you’ll end up with a sturdy bush rather than a straggly one. It’ll take longer, but the results will be worth it.
On the other hand, to ensure that your plant stays healthy you should remove any shoots that cross other ones, or rub against them. Thick growth is good; congested growth is bad.
And get rid of any dead wood!
Where should I make my cuts?
About a centimetre above the the bud whose growth you want to promote. Choose inward-facing buds where you want your shrub to grow more densely, outward-facing buds where you’re trying to avoid congestion or encourage a bit more spread.
Is there anything I shouldn’t prune?
There are a few shrubs and trees which may not respond very well to pruning in every case. But 90% of garden shrubs will be fine, as long as you do it at the right time as described above. And even the other 10% are unlikely to be killed off altogether.
If you’ve got a large tree in your garden and are concerned about its growth, then you may be better off consulting an expert tree-surgeon rather than risk branches crashing down onto greenhouses or worse.