Disadvantages include decreased total yields from each plant and fruit which is more susceptible to blossom end rot and sunscald. Common Tomato Disorders Tomatoes are susceptible to a wide variety of insects and diseases but most can be controlled in the garden. The following is a listing of tomato problems caused by environmental stress. Rot - The blossom end of the fruit blackens and becomes leathery. The problem is caused by a lack of calcium in the fruit due to variable soil moisture conditions.
Prevention involves keeping the soil evenly moist.
Mulches are helpful in this regard. Fruit is perfectly safe to eat. Sunscald - This appears as a white or yellowish spot on the part of the fruit facing the sun. To minimize this problem, never remove mature foliage from the plant. Catfacing - Misshapened, severely deformed fruit, more common on the large fruited or early varieties, resulting from incomplete pollination of the tomato flower due to cold conditions when flowering.