Pruning Workshop
Preparing deciduous trees for the spring rush


In summer your trees will have put on a lot of growth and you probably (should have!)
kept them neatly trimmed. However, once the leaves have fallen in autumn,
you'll find that the shoots have probably grown much more than you realised.

If you want to enjoy your deciduous bonsai in their full winter nakedness,
these over-extended shoots can be trimmed for shape. That's fine for now - but come
early spring, just before bud-burst, you'll need to prune once more.
This time, you prune with the coming season's new growth in mind - thinning out
congested areas and leaving room for further ramification.


 

Trees with opposite foliage

Opposite foliage means opposite buds which, in turn, means that the lateral shoots grow in pairs and at fairly wide angles from the parent shoot. (There are exceptions, such as Circidiphillum, whose laterals grow almost parallel after early shoot pinching in summer.)

  • Widely-spread paired laterals rapidly fill vacant spaces, so the basic branch framework on which they're to grow needs to be open enough to accommodate them.
  • All vigorous shoots should either be cut away entirely or reduced to a short stub - in which case the latent buds around the 'collar' of the shoot will produce shoots.
  • Many of the shorter branchlets that you left last year may have become too thick - these can be cut away completely.
  • Reduce the framework to a minimum, keeping the smaller, finer shoots that grew later in the previous summer.

From the pictures, you can see how drastic this pruning can be. You can also see how the pruned branch will very quickly replace the lost shoots and more.



 

Trees with alternate foliage

Lateral shoots on trees with alternate foliage grow singly (naturally) and generally at less of a wide angle from the parent shoot. They also tend to zig-zag to a greater or lesser degree.

  • Because you only have one bud (therefore one potential shoot) at each internode, you need a rather less open framework than you would with opposite-foliage trees.
  • Here, again, all long vigorous shoots should be either eliminated or shortened to a stub and the shorter, later shoots allowed to remain.
  • Short, late-season shoots have shorter internodes, so will bear more new shoots per centimetre.
  • When carrying out late winter pruning, look very closely and carefully at last year's growth, and that of the previous few years. You will probably see many tiny dormant buds, just waiting for someone to stimulate them to grow by well-considered pruning.

If I had to sum up the principle of late winter pruning in two words, I would say, "Think ahead". Always bear in mind that you are creating a framework for the coming season's growth, and use your observations of last year's growth to anticipate the next.