University of Illinois Extension
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Blossom End Rot
Tomato And Pepper


This is a non-pathogenic disease that is very common during extended dry periods. It begins as light tan water-soaked lesion on the blossom end of the fruit. The lesions enlarge and turn black and leathery. The open wounds can act as an avenue for attack by fungi such as fusarium. This can drastically lower the yield and lower marketability of the fruits. Fluctuating soil moisture supply during the dry periods, and low calcium levels in the fruit are the major causal factors.


Adequate supply of moisture from fruit formation to maturity, and use of mulch (dried brown grass clippings, plastic, straw, shredded newspapers, or plastic) to conserve moisture. Avoid frequent shallow watering – water deep and then wait five or more days before watering again. Proper mulching increases the number of days between watering.


blossom end rot

blossom end rot