Tomato plants slowly dying, can't make sense of it
This is my first year growing tomatoes, and I've got five plants growing in pots on my back porch. They have done really well up to this point, although I haven't gotten more than a dozen or so fruit because many blossoms have dropped off. In the last few weeks, one plant started to turn yellow at the leaves (not from the bottom, but more from the middle and top), then at the stems, then brown at the leaves, and now they are drying up. One by one, each plant started showing symptoms and I can't figure out if this is a disease, nutrient deficiency or watering issue. I've looked over this forum and cannot find a definitive answer. As the plants start to discolor, the fruit stops developing and no new leaves appear. I'm really sad because I've worked so hard to keep these few plants going. I'm watering every day or two because they are in pots and I give them Miracle-Gro tomato food every 7-10 days. The weather has been unseasonably warm, in the upper eighties and lower nineties for weeks.