Proper care and attention is required to prevent begonia from diseases. Make sure that the pot mixture is not water logged, that the fallen leaves are removed and that both the pot and soil mixture is kept clean at all times. If the above mentioned are taken care of, then the Begonias are bound to remain healthy and disease-free.
Rotting is a major concern in Begonias, caused by fungi which attacks the leaves and stem. Two grams of Bavistin mixed in one liter of water should be sprayed on the pot mixture and the plant. It is recommended that while changing the pot mixture or while replanting, the root be dipped in Bavistin for two minutes.