One of my bird of paradise leaves has these ugly black lines on it. Initially, it was just in the center but now it seems like it's spreading across to the edges of the leaf, Is there a way to stop this?Every two weeks I'll wipe the plant to remove any dust. I bottom water it once a week. I keep it in front of the window to get plenty of sun.It's on the top leaf, not sure if it's something I'm doing. I don't notice any bugs on this plant or soil.
I just started caring for this plant since last August, never noticed this until a few weeks ago