This article is the first of two about commonly encountered tomato diseases with suggestions for remedy and prevention. It is a rerun; however, since most summer gardeners grow tomatoes, there is a need to be aware of potential problems and how to correct or avoid them.
Bottom-end or blossom-end rot can occur early in the season as ugly black and brown sunken-in bottoms on the fruit. This malady is due to a lack of calcium, an element critical to fruit development. This calcium lack can be due to drought, inconsistent watering, too alkaline a soil, or persistent high temperatures. Also, calcium may be present in the soil, but an excess of nitrogen and potassium salts due to overfertilization can prevent the plant from being unable to take up the calcium it needs. Either condition can lead to bottom-end rot.