Repotting Tips

We just finished up a great session with the Shohin club talking about pots. Since repotting is upon us, or just around the corner, I thought it would be a great time to throw out some great tips to add to our success and enjoyment this repotting season. These won’t be a formal checklist or set of instructions – just a collection of tidbits. 

Positioning the tree in the pot – this was big question that we went over several times in the Shohin group. Looking at the tree from front to back, the tree should always be placed in the middle of the pot. Always. The roots may prevent you from doing this, but it is always the goal. From left to right, the tree should be placed very near the middle. It may vary slightly to one side, depending on the movement of the tree and the proportions. Never try to balance a poor visual design by moving the tree too much to one side. Rather work on balancing the tree in the design of the trunk and foliage. In a round pot, the tree should go smack dab in the middle. The reasons for these placements are simple. We want to get nice, even growth of roots around the whole tree, so we want an equal length around the root system. When potting deciduous trees in ovals and rectangles, I often cut the root pad back to a circular shape, giving a little more room for new roots. 

Aftercare is one of the most important aspects of repotting, and is easy to overlook. Since I have no greenhouse to protect trees, I tend to start my repotting a little later to avoid frosts. I would start earlier if I could, just when the buds begin to start moving. Root development is happening way before the buds move, but don’t get too anxious with species like junipers and beeches, which are some of the last trees to start growing. Junipers like to have warmer conditions to activate their roots. All of these precautions are so that we can maximize the work that we do at this time. 

With many trees, especially conifers, we may not need to repot for five or six years, so we want to get it right when we have the chance. Speaking of which, if you have an established tree, get it into good soil, then let it settle down for a few years. This will allow all the internodes and foliage to shorten, and allow you to work on balancing out the strength throughout the tree. Aggressive repotting will tend to initiate aggressive growth and may ruin your hard work. 

This is also the time when we can really set the visual direction of the tree with a change in pot, planting angle, and position in the pot. And don’t forget, this is the time to get it just right for an upcoming exhibit. For the pot itself, we can adjust the size – and thus the growing conditions, as well as the style, shape and color of the pot. This is the bulk of what we talked about in the Shohin meeting. You can adjust the pot from Formal to Informal to Casual, from masculine to feminine, and from strong to soft by changing elements of the pot. Those roughly equate from angular to curved shapes, and from dark colors to lighter colors. So from a straight edged rectangular unglazed pot to a shiny cream colored oval, and everything in between.  

If we want a softer rectangle, we can choose one with rounded, or indented corners, or maybe some banding detail. To make it stronger, add an out-curved lip. There are many ways to work this, and of course we almost never have just the right pot. Rarely do I see a tree in too small of a pot. Many times, the pot is way to big, even for just growing on. Keep this in mind. 

As for the great techniques, the best way to learn repotting is of course to do it. If you can learn from one of our available professionals in the area, all the better. It requires some practice and knowhow. Each tree is a slightly different situation, so the more circumstances you can practice at, the better you will be able to cope with the current crisis. This is no more apparent than working with collected material, which hardly ever grows in the prescribed bonsai manner. Their roots are as tangled and irregular as the trunk and branches are on top and require some creativity to get them anchored properly.  Good luck with this year’s repotting.