When to decandle

Depending on our approach, we can decandle all of a tree’s new shoots on a single day or spread out the process over a few weeks (more on that later). This period of time is defined primarily by climate.

Climate

In general, decandle earlier in cool climates and later in warm climates. The following provides a rough guide to when we can start decandling in different parts of the US:

• Cool climates (Seattle, Pacifica) – late May
• Moderate climates (San Francisco Bay Area) – early June
• Warm climates (Los Angeles, much of the Midwest) – mid to late June
• Hot climates (much of the South) – early to mid July

If you’re not sure where to start, seek help from an experienced bonsai enthusiast in your area and, if possible, ask to see their trees to get a sense of how pines respond to decandling in your area.

Tree size

The decision of when to decandle also depends on the size of the tree. The more time summer shoots have to develop, the longer new needles will become. Put another way, if we decandle on the early side, new shoots will have a longer time to develop than shoots decandled a few weeks later. Let’s pause there for a moment….

Black pine foliage

In general, we try to encourage large needles on large trees and small needles on small trees. Very small needles on a large pine would look out of place – more like a white pine, in effect – and might make us wonder about the health of the tree. Large needles on a small tree look unruly and obscure branch pad definition. Developing needles in proportion to the overall size of the tree tends to produce pleasing results.

By decandling large trees early in the decandling season, we give summer shoots adequate time to develop appropriately long needles. By decandling small trees later in the decandling season, we give summer shoots less time to develop, thereby producing shorter needles. Let’s pause again for a moment….

Still with me?

If so, great – you’ve just internalized one of the most important aspects of decandling. It may seem picky to make distinctions as small as a few weeks here or there, but pines respond well to these subtle adjustments, and it is with these subtleties that some of the most beautiful pine bonsai have been created, and by which some of the best pines of the future will be created.