Marin Bonsai Club

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.

Just before his May 7 presentation to the Marin Bonsai Club, Peter Tea wrote on the board nearly the same basic bonsai manipulation tactics he has written up there, and discussed, since his first lecture in our ongoing educational series with him. He listed the three methods of direct manipulation most relevant to the current discussion: Cutting, Pinching, and Defoliation. And then there were the five other main overall ways of inducing change in bonsai: Sun, Water, Soil/Pot, Repot Interval, and Fertilizing.

Not that he was being redundant. Quite the opposite, he was showing the foundation of bonsai methods we have been studying with him for a few years now, and foreshadowing the way in which his talk was about to focus on Cutting and how it really stands alone in contrast to all the other methods he listed. Note that for purposes of his present discussion, Peter minimized his discussion of Pinching and Defoliation, since they’re essentially variations of the same technique: physically altering your tree by removing part of it. His ultimate point was that cutting is a little more dramatic than simply feeding your tree differently or giving it a larger pot, and therefore should be treated as the alternative to those other methods. To emphasize his point, he referred to cutting as “Tactic 2.” The other methods, which Peter collectively referred to as “Tactic 1,” he said may not be as exciting as cutting, but they are ultimately more powerful and controllable in a lot of important ways and should therefore be your first means of altering your bonsai.

But when changes in fertilizer, soil, etc. aren’t accomplishing your goals, it’s time to pick up your tools and do some cutting. And May is certainly the right time of year, because any tree or area of a tree that is getting too much energy will be growing like gangbusters. May is a real busy time for owners of deciduous trees.

Peter makes a point to differentiate between cutting and thinning. Cutting a branch back causes division, which leads to ramification and other desirable aesthetics, but it also slows the tree down, which is often the only real reason for cutting back the branch of a fully developed tree. Thinning, on the other hand, is not just a more widespread approach to removing growth tips from the tree, it’s an important method for revigorating what’s left after you’ve trimmed. What’s left will be stronger, an effect that is particularly helpful if that area was struggling.

This cutting/thinning distinction set Peter up for his conclusion later on, when he discussed the way interior growth can suffer despite your isolated attempts to cut back the ends of the branches. If you’re trying to encourage an individual piece of secondary growth to divide and thrive, cutting the end may not be enough, because the tree still does not consider that area to be part of the exterior, or canopy of the tree. In other words, even though there’s nothing growing further out on that particular branch, and you may have cut areas back above, the fact remains that, in relation to the rest of the tree, it’s not at the “outside” of the tree, which is where the tree wants to put its energy. That is why sometimes you just have to cut way back all over the tree and essentially start over. The way Peter puts it, sometimes you just need to “make the inside the outside.”