Answer: The wet weather has been causing some fungal and bacterial problems to take hold and this can really spread in tightly spaced plantings. The little begonias you planted are usually set about six inches apart to allow for mature size, so spacing could be a bit further assuming they were quite small when you planted them -- better air circulation helps a lot in limiting infection. (You could transplant a few to another container, maybe.) Sunshine or at least a break in the rainy weather will also help a lot. In the meantime, clean away all of the infected foliage and blooms to eliminate the source of reinfection as best you can. Then avoid overhead watering whenever possible and make sure you are not overfertilizing the plants as this can result in excess soft and leafy growth that is more prone to infection. If the problem persists, contact your county extension for the most up to date recommendation on a fungicide to use.
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