Overall, my tomato plants look great -- the tallest three or four are already taller than their 5 foot cage (made of concrete reinforcement wire). But I have noticed that down bottom on some of the plants (specifically, the ones with the most leaves and tomatoes on them) that the leaves are turning yellow or brown and just sort of drying out. I water my garden every other day and use a garden hose with a long wand to do it. I stick the wand down in that area to water so that I don't have to wet the entire plant. Might this be causing the problem? Or is it something else?