Begonia Blooms Develop White Or Grayish Spots And Brown Crunchy Edges

Question

Q: Dear Nancy, I have wrote twice to the American Begonia Society and they have yet to answer back. Frustrating. Anyway, I have 4 flats of the Bronze Leaf Scarlet begonia plants planted in my yard. The tiny red blooms keep developing a white or grayish spotting on the blooms, and if left to grow on the plant, they actually get black on the edge. Also, some of the leaves on many of the plants have brown, crunchy edges. This is driving me nuts, I keep picking off the red blooms that are discolored and try to tear away the edges of the leaves! What can be the cause, and more importantly the treatment for this. Please help!

Answer 1

A: Your begonias have a disease called powdery mildew. This fungal disease is quite common. This web site will tell you what you can do treat it and prevent it next year.
http://homeguides.sfgate.com/white-spots-begonias-27161.html
Good Luck. Nancy