Physiological disorder (not a disease) caused by calcium deficiency in developing fruit. Common in tomatoes and peppers.
Dark, sunken, leathery spots on blossom end of fruit. Spots may enlarge and become moldy. Affects first fruits most severely.
Calcium deficiency in fruit tissue due to inconsistent watering, root damage, or excessive nitrogen. Soil calcium is usually adequate.
Not infectious - caused by environmental and cultural factors.
Inconsistent watering (drought followed by heavy watering). Rapid plant growth. Root damage. High nitrogen fertilization. Sandy soils.
Consistent watering schedule. Mulch to maintain soil moisture. Avoid excessive nitrogen. Don't cultivate near plants. Test soil and add lime if needed.