A friend of mine has three tomatoes in pots and they recently stopped growing. The stems have started to droop, leaves are curling and the ends of many stems are disfigured. This all seemed to happen rather suddenly after a couple of weeks of significant rainfall. Previous to the rain the plants had been growing rapidly and looked good. He was watering when the soil felt dry. We are located in central Oklahoma and the weather has been in the mid 90s for the last week or so. Any advice?