I live in what is known as California is central valley. Just far away enough from the bay area to get a USDA 9. Very Mediterranean. This fall has been unusually warm but not particularly hard. We just left the 80s/90s and are now experiencing 70/80° days, And 45 to 55° evenings. This specimen came in the mail from a well-known on line bonsai nursery and had already shed a number of its leaves. Nevertheless I’ve been watering it and fertilizing it and it has sprouted new growth. But the problem that seemed to have come with it persists. As you can see from the photos the leaves remain green but then spots and edges will turn ruddy then brown at the Tips and you know the rest. It has never completely dried out. The water pH is around 6.5 with a low total alkalinity. The only problem I can think of is too much direct sunlight. Maybe? I’m open to any suggestions. Thanks guys.
I live in Livermore, my experience with trident foliage that looks like that has been poor balance of water and Oxygen. I have a couple tridents about the size of yours that have had the same symptoms. A spring repot in 2:1:1 akadema lava pumice has been the trick for me.
Thanks Garrett. I was already thinking of a repot in the spring but I have good percolation but, come to think of it, when I test the soil it is frequently driy from tthe edges in and moist nearer the trunk. I wondered if that reflects a practice of reporting the tree in its native soil and filling in with akadama around the edges. Perhaps I will just wait till after leaf drop to repot. Thanks again for the reply.
I would be backing off the fertilisation as your coming into fall. Definitely re pot too when you can.