Tomato problem

[elmosmom]

We have four Heirloom tomato plants that were doing very well. Today I noticed that the blossoms are shriveling up and turning brown. We have never had so many problems.

 

[shoes99]

We have four Heirloom tomato plants that were doing very well. Today I noticed that the blossoms are shriveling up and turning brown. We have never had so many problems.

I have two Jersey tomato plants in pots. This AM I noticed that the larger one has shriveled leaves...yikes, hope I didn't over water them.
How often are you supposed to use miracle grow for tomatoes?