Pruning Serissa bonsai
Snow rose bonsai (Serissa foetida) grow 5-10cm per month in the summer months if they are optimally cared for and provided with sufficient bonsai fertilizer. For this reason, it is usually necessary to cut twice, often even three times during the growing season.
Before we prune a Serissa bonsai in our bonsai nursery, we usually wait until the growth has reached almost 10cm. The bonsai may look a little out of shape, but it can recharge its batteries for the next budding.
Under our conditions, we are usually prune a Serissa bonsai at the end of May, mid-July and sometimes even mid-August. We do not cut later because the days will be noticeably shorter and the bonsai tree should not be weakened by a new cut before winter.
The first picture shows the development of a Serissa bonsai from May (shortly after the 1st cut) to July (2nd cut). Especially in the upper part the tree has become noticeably more dense and the degree of ramnification has increased.
Serissa bonsai development May-July
Since the shape is usually already predetermined and should be maintained, pruning a Serissa bonsai is very easy. It is very reminiscent of cutting a hedge.
Since the branches of the Snow rose are very thin, a standard bonsai shear is sufficient for pruning. With this you can cuts the Serissa crown along a previously imagined line.
Planning
The first step in pruning a Serissa bonsai is planning. Depending on the quality of the tree you have to look ahead to see what the bonsai tree should look like in a few weeks, months or even years.
Since the instructions are intended for bonsai beginners, the pruning of a largely pre-designed Snow rose bonsai is explained here. I.e. you bought a finished bonsai, it has grown a bit and now has to be prune back into shape.
Serissa bonsai pruning - Planning
In this case you first have to consider how high the bonsai tree should be in the future. The pruning must then go much deeper, otherwise the tree will get bigger. The less the tree is branched, the deeper it has to be cut back.
In the example shown there is already a clearly visible and branched crown. In such a case, probably typical after a purchase, planning is very easy.
If the crown should go up to the blue line in the future, you have to cut the Serissa bonsai back to the red line. Not much deeper, otherwise too much of the existing fine ramnification will be cut away.
Pruning of the crown
Now you can start pruning the bonsai. Simply lay the bonsai scissors flat on the crown and cut along the previously considered, red line.
Cut back of the crown
You can also cut each June snow shoot individually. In our experience it takes significantly longer. But the result doesn't look much better.
Forming the branch pads
You can also cut each shoot of the Serissa individually. In our experience, it takes significantly longer. But the result doesn't look much better.
Pruning the branch cushions
In the next step, the branch cushion are shaped a little. The cushion pads should set itself apart from the rest of the crown.
However, the upholstery should not stand out too clearly. Otherwise you have a "cloud tree" as you see it in many front gardens. This has only little to do with bonsai design as is commonly understood. The bonsai then looks very artificial.
Revision (cleaning) of the undergrowth
After the pruning, the undergrowth will be revised.
Revision of the undergrowth
Above all, typical weeds like Irish-moss (Sagina subulata, scottish moss), Hairy bittercress (Cardamine hirsuta) or, as we can see here on the picture, Common liverwort (Marchantia polymorpha) should be removed. These weeds grow particularly quickly if you give a lot of nitrogenous fertilizer.
A Serissa bonsai may need to be pruned again in mid-August after this cut (the 2nd in the year). After that it can grow until next spring without being pruned again.
Most common mistakes
Many bonsai friends do not really dare to cut deep enough into the crown when cutting their Serissa bonsai. They usually prune far too little.
The consequence: Not all final buds are cut off. These continue to grow, become stronger and take the lead. New buds sprout out of the cut shoots are clearly sparse. Individual cut shoots can even wither.
Pruned Serissa bonsai tree
What is the reason for that ?
The tips of each branch produce growth hormones. These growth hormones are transported downwards. There they inhibit the grow of buds.
This peculiarity of growing above all on the top is called Apical dominance. Above all, the tree wants to grow upwards and quickly higher so that it is not shaded by other trees.
If we prevent apical dominance by consistently pruning the tips of each shoot (especially in the upper area of the crown) the "sleeping buds" in the lower area and inside the crown will sprout better and more vigorously. This leads to the desired better ramnification.
In addition, if you cut not deep enought, the crown is getting bigger and bigger from cut to cut. This is usually not wanted and can be corrected later only with difficulty.
Therefore: If your Serissa bonsai is healthy and the time is right (May-July) - you dare to prune deep enought.