05/20/2026
“What’s going on with my tomatoes?!” Tomatoes are the most popular vegetable to grow in Mississippi, so we get a lot of calls when gardeners have questions!
This is a helpful cheat sheet of common problems with tomatoes. We have a great Extension publication that explains in further detail the most common disorders and methods of prevention. You can read it here: http://extension.msstate.edu/publications/tomato-troubles-common-problems-tomatoes
BLOSSOM-END ROT
It appears as a dry, leathery (not mushy), dark brown or black area, usually at or near the bottom of the fruit. BER can sometimes occur on the side of fruit, and occasionally only on the inside, so the BER is hidden until the tomato is sliced open. Sometimes the spot is sunken, and these tomatoes often ripen before all others.
BER is not caused by an infectious agent (pathogen) and is, therefore, not a disease. It is a physiological disorder caused by lack of adequate calcium in developing fruit. It’s common to see BER on the first tomatoes of the season. While low calcium in fruit is the cause, the real culprit is often drought. Without a steady supply of water, the tiny root hairs dry out, which limits the amount of calcium the plants can absorb and supply to developing fruit. Don’t let plants wilt between waterings. The best way to prevent damage to root hairs caused by drying out is to provide consistent water and to mulch around plants.
FRUIT CRACKING
Cracking is a common problem in tomatoes when growing conditions are not perfect. Cracks can be described as radial—those that radiate from the stem end and move downward—and concentric—those that form rings around the stem end of the fruit.
Both types of cracks are signs of inconsistent water content in the plant. Uneven watering will promote fruit cracking, so be sure that plants are getting enough water. Cracking can also be promoted by very fast growth, excessive moisture (rain or heavy watering) after a dry period, high temperature, a large difference between daytime and nighttime temperatures, and inadequate nutrition.
Not all cracking can be avoided, but the severity can be lessened by mulching, maintaining an even water supply, and using an adequate fertilizer program. Some varieties are also resistant to cracking.
UNEVEN RIPENING
Uneven ripening includes green stripes, streaks, or blotches; stars on the bottoms of fruit; and yellow or green shoulders. Sometimes, one wall or one portion of the tomato will remain green or white even after the rest of the tomato turns red.
This problem may be caused by a number of factors, so the exact cause can be hard to determine. Most likely causes are high fertility (usually nitrogen), low potassium, high temperature (the red pigment, lycopene, is killed around 93°F), infection by certain viruses, and sweetpotato whitefly feeding.
Be sure to maintain adequate nutrition by soil testing and applying fertilizer according to the recommendations. A tissue analysis can help reveal if the cause is nutritional.
CATFACING
Catfacing is a condition in which the fruit becomes malformed or irregularly shaped, often with brown scars at the blossom end that sometimes run up the sides of the fruit. The blossom end of the fruit will often be puckered with deep crevices. This is different from BER, which shows up as dark brown areas on the bottoms of fruit but without the puckering or crevices.
In its most severe form, the bottoms of fruit seem to be turned inside out so that the seed cavity is visible on the outside. It usually only affects the earliest fruit set due to the cooler temperature at that time; later-harvested fruit are generally not affected. Catfacing does not affect the edibility of the fruit. The scars can be cut off and the rest of the tomato eaten.
Catfacing is almost always caused by cool temperatures during pollination and early growth. Some varieties are more susceptible than others. The only management methods are to plant later in the season, use resistant varieties, and use plastic or spun-bound row covers to increase temperature on cool days and nights.
