Bonsai Growing Tips: Clippings from July 2025

Where did that mild and pleasant weather go?! When you’re reading this, it’s mid July and daytime temps are consistently in the 80s. It’s warm, but not crazy hot yet, and that means there is still work to be done — here is a look at what I’m up to this month.

Dwarf Jade/Elephant Bush (Portulacaria afra): These plants love the heat, so this is a great time to be working on them. In fact, I’ll be defoliating some of mine this month to edit the structure and kick off a new round of growth. It feels a bit wrong to defoliate a succulent for the first time, but I promise they grow back quickly. This species lacks a distinct petiole (leaf stem) to cut, so be careful when removing leaves that you don’t damage the dormant buds at their base.

This species can also be repotted now, and they are very tolerant of major rootwork. Unlike other popular bonsai species, I like to hold off on watering after repotting them, until I see new growth extending again (it’s ok if they get a bit wilty).

Japanese Black Pine (Pinus thunbergii): If you haven’t decandled your black pines yet, it’s time. By the time the next newsletter comes out, it will probably be too late. Some folks like to wire them now as well (right after decandling and needle-pulling), or you can wait until the fall/winter work, but don’t mess with them in between, since the newly forming shoots will be very delicate for the next couple of months.

Crape Myrtle (Lagerstroemia sp.): Mid to late summer is usually when I get flowers on Crape Myrtle Bonsai. By now, I have trimmed extending new growth several times, but if I keep trimming into July, I may start inadvertently cutting off flower buds. So, as soon as I see the first buds forming, I stop cutting new growth for a bit (if I want to let the tree flower). If you do a good job balancing and ramifying the tree, the flowers should open close to the branches, not way out on the ends of 2-foot-long shoots.

Junipers: One of the best things about Junipers is that you can work on them most of the year, so I tend to slot my juniper work in between more time sensitive things (like repotting, decandling, etc.). Right now, it’s mostly scissor work for me — removing scraggly hanging growth and crotch shoots, removing runners, and thinning dense areas. Summer is also a pretty good time to create jin, since the tissue is full of water and will peel from the deadwood much more easily than in fall or winter. Remember that crummy branches often make crummy jin, so consider developing a branch to have movement, taper, and ramification before killing it off to make more interesting deadwood.

Odds & Ends: Bougainvilleas are growing like crazy and can be pruned all through summer. Many broadleaf trees, like elms and boxwoods, will continue growing (and getting pruned) throughout warm weather as well, but some delicate species, like Japanese Maples, will slow way down in our dry heat. If they stop growing, I stop cutting. I’ll start to think about defoliating deciduous trees next month . . .

Remember to keep both yourself and your trees well hydrated this summer — it’s only getting hotter from here!