with tomatoes the problem is caused by a variety of circumstances.
Often the seedlings are already buried very deeply, which is preferred by a lot of growers but I always knock off the extra soil and plant them at the root flare level.
Tomatoes like their heads hot (lots of sun) and consistent watering. They also don't like their roots consistently wet. So with the rain we have had it's difficult to sustain the conditions they prefer. What's the answer? No one has the absolute answer, of course, but I have had great success with the program I outlined in my previous post.
Treat with cornmeal around the base. The cornmeal helps the soil become more particulate, which aids drainage, oxygen availability and root growth. The garlic repels small sucking insects and helps in the overall health of the plant. Foliar feeding for tomatoes makes all the difference in their condition during these hottest months. I use Bioform liquid or Garrett Juice because they have the broad combination of nutrients that is most consistently beneficial.
My plants have also suffered from wind, hard rain and hail damage but they are still healthy and still producing daily. That kind of reaction is convincing enough for me!
Kathe