I bought the two tomatoes pictured here on the same day, from the same vendor and have fertilized and watered them in nearly identical ways. They are different varieties, but each tomato came in the same size pot, a 4-incher. So what happened? Why does the tomato on the left look so sad, even though it is working hard to ripen a handful of fruit? And why does the tomato on the right look so–well, lush?
Most likely culprits: Disease or depleted soil. The tomato on the left is planted in one of my ground-level beds, a bed in which I have grown tomatoes for several years. Perhaps the nutrients tomatoes love have been pulled, and pulled, and pulled out of that soil, even though I add compost to it each year. (Think Irish potato famine or the Dust Bowl for more devastating examples of soil depletion from monocultures.) More likely, the poor performance is due to a soil-borne disease, as this paper from Iowa State indicates. The tomato on the right is in my newest raised bed, enjoying lots of fresh black dirt and piles of compost from the local compost pile.
My plan is to let the poor guy on the left produce his tomato or three, and then pull out the plant, disposing of it in the trash rather than the compost, and replanting the bed with something from a different plant family. Since we are late in the season, I may try a quick-growing green bean or chard. Next year: No tomatoes in that bed.