This year I put it in a mix of akadama kanuma and pumice with a dash of charcoal. They are an acid loving plant. My guess is about 40%A, 30%-K, 30%-P. I repot it in mid to late February which is when it starts to grow vigorously again. My growing area stays fairly cool for winter which is why it slows down. You can repot in summer, I just like mine to be recovered by July August because that’s its best flowering months.
Once you get it into bonsai soil you’ll have to water every day sometimes twice. I’ve had mine drop 30-40% of its leaves from getting too dry. It was in an exhibition where watering can be sparse and when I got it home dropped 50% of its leaves. The leaves never looked wilted. I have the ability to water it on demand, but you may want to consider this when you choose a bonsai mix.
I don’t know if you’re aware of its thread so here’s a link.
So here's a Grewia post. History- Started from a cutting 1991. Nurtured as a flowering ornamental by my mother until 2012. I would give periodic haircuts once or twice a year on my visits. These haircuts implied bonsai. The grow was always long and leggy because of how the flowers form. First...
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