Pruning your bonsai

Pruning is part of the gestures you will have to do regularly on your bonsai to allow it to keep its proportion. Whether it is to shape it or simply to keep it to a wished shape, pruning is essential!

Why do I need to prune my bonsai?
Pruning allows to shape your bonsai and to keep its proportions. It is essential to well respect the balance between the aerial parts and the roots part and that’s thanks to pruning and repotting that you will achieve this. In this way, you will be limiting the growth of the young, vigorous shoots.

When do I need to prune my bonsai?
Structural pruning is usually done at the end of winter, or at the very early spring before the sap starts going up. This harsh pruning will only be necessary if the bonsai needs reshaping (shaping a young specimen or working on the shape of an older one). It must not be done the same year than a repotting year.
Maintenance pruning must be regular from spring up to the middle of summer for most species. For spring flowering bonsais, wait until the end of blooming to start pruning. For bonsais which only bud once a year (Spruce, Beech tree…), one pruning will suffice.

How do I need to prune my bonsai?
Pruning principles differ according to each variety, so, it is a good idea to learn about the variety in question before getting into it. For structural pruning, the aim is to simplify the branches only keeping two branches on each ramification. For maintenance pruning, you have to keep the bonsai’s shape while maintaining foliage and dense ramifications. As novices, we have got the tendency to prune a branch as soon as it has got two leaves, yet this does not allow a good ramification and leads to a lengthening of the branches which is not at all desirable. Wait until the branch has 6/8 leaves or pair of leaves to cut back to 2/3 leaves, so, all the vigour brought to this branch will encourage the appearance of new ramifications and the conservation of a thick foliage.
Therefore, in practice, you have to wait long enough between two pruning’ sessions to get highly vigorous branches. In all cases, it is essential to use clean, sharpened tools. There are lots of different tools for pruning bonsais and it is not essential to have them all, but you will see with practice that you will be looking for such and such tool for such and such type of work.

A few tips: Only do a structural pruning if the tree needs it; as for maintenance pruning, it is done regularly but do not haste, only use clean, sharpened tools.