Cast Iron Plant
The rear surfaces of our leaves have small black specks and the plant is not a happy one the. The leaves have brown tips and some need removing. Any help.
Interesting, because Cast Iron plants don't typically suffer from any diseases. Black spot fungus is the most common ailment that causes the symptoms you describe (assuming the black specks are actually part of the leaves and not insects). At a minimum, you'll want to remove all the affected leaves. If the spots are all over the entire plant, it might be necessary to use a fungicide (no guarantees, though).
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