I bought an hibiscus plant in december last year form home depot; it is a braided tropical hibiscus - assorted; I keep it near the window (south). No yellow leaves. Temperature 19 - 20 Celsius, soil moist but not excessively. Everythig looks ok except it has no fowers. Is the plant dormant? Too many leaves-not enough stamina left for flowers? Am I doing something wrong? Please help.