the white stuff could be "white fly".9 k! u( s7 V+ o( ?0 g' L+ H* r
I had the same problem before. It because your plant is too wet. I showed the leaves twice a day for a whole week, then the white filies were all gone. # l8 }; R% B3 f7 `1 hHibiscus is a typical plant, show helps a lot.