On Monday, I discovered that our mystery tomato plant (which clearly seems to be a plum tomato of some sort) had tomatoes that had blossom end rot. In my container garden, this is usually solved by an application of lime. It seem like for tomatoes in the ground this is caused by a lack of calcium uptake by the plant caused by uneven watering. We need to pay more attention to watering the tomatoes. Odd, however, that this seems to be occurring on only 1 of our tomato plants.