October 2025 Bonsai "Growing Tips" Column

Well, they’ve been serving “pumpkin spice” lattes since late August, so who knows what season it is now . . . I expect to see holiday decorations going up even earlier this year, as Christmas makes is inexorable march toward July, but don’t rush your bonsai into winter. Trees are still growing here in SoCal, and there is plenty of work to do!

I’m Still Fertilizing: I am still seeing some good “second spring” growth on many of my bonsai, and that means continuing to fertilize. Lots of un-localized advice might suggest that you stop fertilizing as early as September, but with our exceptionally long growing season, I usually continue well into November for most trees. I’ll probably start again around February, leaving only December and January as fertilizer-less months. If you have indoor trees, they can be fertilized year-round (with something very mild/low-nitrogen). I stopped fertilizing black pines after cutting candles. If the new growth has hardened and stopped growing, a bit of fertilizer can be added now without danger of leggy extension; this gets extra resources into the tree to kickstart vigorous growth next spring.

Black Pines: I like to do my black pine cleanup near the end of the year, but you can start now (especially if you’re planning to show the tree next month) as long as the new needles have hardened off. This work includes pulling the remaining old needles and selecting buds: where candles were cut, there should now be new shoots. If there’s only one, that’s a bummer, but there’s nothing you can do about it now. If there are two, then great, we’re done. If there are more than two, I will select two (and only two) to keep while cutting off all of the extras. Usually I’ll try to keep two of matched medium strength, removing the longest (strongest) and shortest (weakest) shoots if possible. Once a pine is needle-pulled and bud-selected, it is a great time to wire . . .

Wiring: As the weather continues to cool and growth of temperate conifers slows (e.g. junipers and pines), branches can become more flexible. Fall is a great season for wiring, especially for large bends that would be more dangerous during warmer weather. There is still enough growth activity to heal any damage done before winter dormancy kicks in.

Cleaning Up Trees To Show: In addition to cleaning up pines, any tree that needs to look its best this season should be “cleaned.” That means removing old/damaged foliage, cutting off hanging “bottom-side” growth, and cleaning new shoots from the crotches of branches.

Finally, I always recommend that my students rank their trees. Take a good look at your collection and really think about what your best trees are, what raw material has the most potential, and what trees may just be hanging around. It may seem ruthless, but time and space are precious, and your collection should improve as your skills do . . . With the holidays approaching, now might be a great time to think about passing on some bonsai to family, new club members, or other beginners who can learn from and enjoy them as you did!