Why are my bougainvilleas losing their leaves?

I have a few bougainvillea's, planted at different times in different locations, and they are all losing their leaves. Why is this?


I live in S. Florida where it is pretty hot, but bougainvillea's like the heat. It has been raining a lot lately and I know they do not like a lot of water, but i wouldn't think that would make them lose their leaves. I also know that if you put them in shock, they will usually bloom.


Why are they losing their leaves and how can I make them regain them and also bloom?

Why are my bougainvilleas losing their leaves?
I don't know about bougainvilleas specifically. However, all plants have a natural cycle. Could it, perhaps, be because it is approaching the end of summer?