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Hi all, still learning about bonsai but a couple weeks ago I repotted my small ficus using a mix from
Since then some leaves started turning black as well as the branch end as in the photos. A while back some branches started like this and eventually the bud went entirely black/died. Any idea what causes this? Watering/drainage issues?
Thanks,

Working on the roots of a plant that is not really healthy, like a ficus in winter, or trimming roots too much, or keeping the rootball too wet may do this.