Blossom End Rot
This problem spreads through handling, insects or soil rather than the weather, so there is no live forecast risk — focus on prevention below.
When it strikes
About
Blossom end rot is a physiological disorder of tomatoes, peppers, squash and melons caused by a calcium shortage in the fruit, usually triggered by uneven watering rather than low soil calcium.
Symptoms
A sunken, leathery, dark brown-black patch at the blossom (bottom) end of the fruit, often on the first fruit of the season or during dry spells; the rest of the fruit may ripen normally.
Organic Treatment
Keep soil evenly moist with mulch and consistent watering, which is the real fix; foliar calcium offers only minor help. Remove affected fruit.
Chemical Treatment
Calcium chloride foliar sprays give limited relief; the disorder is corrected by water management, not chemicals.
Prevention
Water deeply and consistently, mulch to buffer moisture, avoid heavy nitrogen and root damage, and ensure adequate soil calcium and pH.