I have had several reports recently of blossom end rot. This is a decay on the blossom end (the opposite side of the stem) of your fruit. This is not a pathogenic disease, but instead a nutrient deficiency problem. Unfortunately, this phenomenon can still take a large toll on your crop, with losses of 50 percent or more in some years.
Blossom-end rot affects tomatoes, peppers and eggplants. On the tomato and eggplant, the lesions begin as a small area that appears water-soaked on the blossom end of the fruit. This stage begins while the fruit is still green or during the early ripening process. As the lesion develops, it will enlarge and take on a sunken, black, leathery appearance. In peppers, the affected area appears tan.
This disorder is caused by a low concentration of calcium in the fruit. Fruit production requires a large amount of calcium, and when there is not enough, the tissue begins to break down. This results in the sunken lesions found on the blossom end of certain vegetables. Most of our soils have plenty of calcium in them. The problem is that the calcium can only be taken up when water is available. So to avoid this problem it is important to keep the soil evenly moist. I think one reason it is showing up all of a sudden here is because we have gone several days without rain. The plants became used to the constant moisture we had been receiving. A few days of dry caused stress.
Rapid growth of the plant due to high nitrogen levels can also contribute to this disorder.
To avoid this condition, make sure that adequate amounts of water are supplied to the plant. Avoid planting too early or in cold soils. Do not cultivate within a foot of the plant or deeper than one inch. This will help to maintain feeder roots. Also maintaining a soil pH of 6.5 to 6.8 will increase the amount of calcium that is available to the tomato plants. Using a mulch around your plants, such as newspaper and straw can also help as it keeps the soil more evenly moist.
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