My ficus bonsai has these brown spots:
It's only a few leaves, but obviously I want to get ahead of it. Preliminary Googlage says that this can be caused by bacteria or fungi or insects: how can I tell which it is, so I can treat the problem correctly?
Looks like insect or fungi damage, you could prune the bad leaves off then spray the rest of the leaves with any kind of leave spray or homemade dish soap + water mix. If you use a homemade solution, spray top and bottom of the leaves and let it sit on the leaves for a few mins then spray it with water to wash it off, once a week until everything looks good.
