Restoration pruning of my small tree
On the pruning course that I used to run at Harlow Carr Gardens in Yorkshire, I would include the following points:
- Don’t be scared of having a go, shrubs are tough, you will do them little harm.
- Any harm is likely to be aesthetic: when you have finished pruning, your work should not be obvious to the casual observer!
- Pruning cuts should be within the complete volume of the bush: if your cuts are all on the edge you have done it wrong.
- As you become more confident you should take out big pieces, not lots of little ones.
- Restoration pruning of old shrubs can be done at any time of year. Even if some flowers are lost, those that remain on your now elegant shrub look so much better than they did before.
- Never leave bare stumps at the end of pruned shoots.
Ten years ago my sophora was planted as a shrub 30cm high. Some plants do have a tendency to grow! Formative pruning changed as the shrub became bigger. If you allow it, what was a multi-stemmed shrub will, over the years, become a small tree. My tree threatened to become unsightly so one of the two remaining trunks had to go.
Heavy branches should be dismantled before making the final cut.
The last cut should be at the base of the branch leaving a natural shoulder. It should NOT shave into the main trunk. But why is it black?
After removing the large secondary trunk, a large branch high in the tree spoilt the new outline. It had to be cut back to a new leading branch. I can best illustrate the principle with this much smaller shrub.
A leading shoot grows over my lawn.
Cut it out to a new leading shoot.
Three weeks later it is still alive!
And did my pruning pass the ‘casual observer’ test?
I had rubbed soil on the wound to disguise the large white cut (this is not so silly, a common soil bacteria, Trichoderma viride, is antagonistic to wood decay fungus).
Brenda returned from her holiday, walked the garden and saw nothing! Fortunately she approved when I confessed.