Marin Bonsai Club

Peter Tea joined us in August to talk about the work that is appropriate to do on junipers late in the summer. He brought three Kishu Shimpaku junipers with him, plus an olive for contrast, and to illustrate how different trees need different approaches.

Peter began with a quick recap of the importance of working on healthy trees, listing once again the six things we can manipulate to ensure that we get the most out of our trees and the changes we make to them: sun, water, soil, repot interval, fertilizer, and cutting.

The Kishu Shimpaku is, like most junipers, highly valued for how great it looks with foliage pads, those perfectly shaped bundles of foliage that are so iconic in bonsai. As he drew front and side diagrams of them on the whiteboard, Peter pointed out that creating those perfect pads always begins with branch division, lots of division. But it’s not enough to just create division, it must be planned carefully. For instance, you have to bear in mind that all that division will add girth to the tree. Depending on where you begin the division, that girth will either be close in to the center of the tree where it looks good, or it will be far out at the ends of the branches, where it will only look good in the most extreme of compositions.

With that in mind, Peter turned to the least developed of his junipers and asked the audience to imagine where we would want the outer edge of the final canopy for that tree. He held his hands open around the tree to help us envisage where its perfect silhouette would be. With that goal established, he told us to imagine how much further in we would have to start dividing the tree’s branches to allow enough division and subdivision to create the dense pads achieved on a mature tree. He moved his hands in to where that would be, and many of that tree’s young branches were already bare beyond that point. Clearly, some of those branches were going to have to be sacrificed. Peter’s ultimate point: you might have to cut deeper into the tree to get the ramification to peak where you want it. Additionally, he added that you can’t work on one isolated area without regard for other areas, or else you’ll waste your time perfecting something that might end up getting sacrificed in service to the larger design.

Returning to the importance of working on healthy trees, Peter sidetracked to a discussion of spider mites and how to deal with them. Various types of oil are effective. “Year Round” and “Neem” are two popular examples. Peter recommends using only 60% of the listed dosage and avoiding using oils under direct sunlight. Douse the tree thoroughly, but then wash it off an hour later, again to avoid sun exposure. It will have done its job of suffocating the mites within that hour. Be sure to repeat the process a week later to catch new hatchlings. According to Peter’s experience, miticides (Floramite, Sultan, Hexagon) are less successful in the long run, the problem being that mites build up resistance to them over time. Peter also says that Malathion doesn’t work at all.

Our June presenter was Bill Castellon, a professional landscaper, aesthetic pruner, and shohin fanatic with extensive experience growing and pruning pines of all sizes and varieties. The topic of the evening was decandling black pines and Bill brought a vigorous young black pine for demonstration, which was raffled off at the end of the night.

Bill went straight to a discussion of decandling timing strategies and never gave the down-and-dirty on what decandling is and why it’s important. A quick explanation for those newer bonsai enthusiasts reading this: Decandling a pine means cutting the new growth shoots of a vigorous pine, referred to as its candles, so that when the needles developing inside of them open up later, they are noticeably shorter. It is done because simply cutting the needles after they are fully developed will result in unsightly brown tips on the needles. The proper timing of this procedure is a topic of much debate, with as many opinions as there are microclimates in the San Francisco Bay Area, but the one agreed-upon constant is that the later you make the cut, so long as you don’t wait too long and miss the developmental window, the shorter the needles you will get. Decandling is also done to encourage division, being the pine equivalent of tip-pinching on deciduous trees.

Like many of our other favorite presenters, Bill does not like to state absolutes like, “You must decandle in June.” Rather, he likes to set general guidelines and emphasizes that you must consider the individual tree and its specific environment. As an illustrative example, he points out that shohin artists in Japan wait until as late as July 15th to decandle, to get exceptionally small needles. They can do that there because their climate supports it, but here in the Bay Area, Bill suggests we don’t push our pine candling past July 4th at the absolute latest. If you decandle your pines too late, you’ll get malformed or otherwise unhealthy needles, or even an entirely failed growth tip that eventually withers and dies. When in doubt, or if you absolutely must go by a specific date, Bill says that June 15th is a safe time to decandle pines in our area.