I had no clue about this

Blossom end rot is a physiological disorder that manifests as a dark, sunken spot on the blossom end of the tomato fruit. It is primarily caused by a calcium deficiency in the developing fruit, often exacerbated by inconsistent watering, which affects calcium uptake. This condition not only affects tomatoes but can also impact other fruiting vegetables like peppers and eggplants. Recognizing the signs early and understanding the underlying causes can help gardeners take preventive measures to protect their crops.