the white stuff could be "white fly". 0 V# u' X: e6 a8 ?# v5 X) V. O4 oI 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.& Z7 S- p6 F1 `0 m: {" U
Hibiscus is a typical plant, show helps a lot.