Karen Delahaut, Walt Stevenson
Even though symptoms may not appear until after harvest, many of the disease-causing organisms that cause fruit rot infect tomatoes before they ripened. Once fruit is infected, little can be done during harvest or storage to reduce the damage. Most fruit rot fungi and bacteria also cause foliar diseases, so management throughout the season is critical not only to produce a healthy plant and high yield, but also to provide high-quality fruit. This fact sheet will show you how.
Not all fruit damage is caused by diseases. Environmental factors such as calcium deficiency or poor fertilization may also blemish fruit.
For a description of some of the most common problems, see Extension publication Tomato Disorder: Physiological Fruit Problems (A3798).