the white stuff could be "white fly". 6 f( k5 |6 D5 D% X% mI 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.( s# I1 v9 d/ h, J. [. |6 l
Hibiscus is a typical plant, show helps a lot.