To corrupt totally the famous Charles Dickens line — it will soon be “the best of times and the worst of times for tomato gardeners.” Late in June and into July is the time tomato growers wait for: harvest season. For some, however, this long-awaited gathering of the crop can end in disappointment. This is because many ripe tomatoes will be scarred, disfigured, or otherwise rendered less than perfect.

Disease is the first problem that comes to mind. So, out comes the sprayer with a fungicide. But it doesn’t work. A possible second cause of fruit troubles is insects. So, out comes the sprayer again, full of an insecticide. And it doesn’t work, either.

So, what caused your once promising tomato crop to turn out looking so unappealing? Rather than diseases or insects being the culprits, there are several physiological problems that can cause tomatoes to develop imperfectly, and knowing what they are will help you to eradicate them. Listed below are the most common disorders that occur right around harvest time, as well as tomato growing tips on how to deal with them. Study them carefully to get this summer’s tomato patch back on track.

Blossom End Rot: This ugly, brownish blotch on the bottom of an otherwise perfect fruit is undoubtedly the most common tomato ailment. This problem stems from stress put on the plant due to frequently alternating wet and dry conditions. A three- to four-inch mulch will help stabilize the water supply and prevent the rot from occurring. A shot of calcium will also help stop stress on your tomato plants. Powdered lime is a good source of calcium, but it reacts too slowly with the soil. So for quicker relief, spray the tomato leaves with a diluted solution of calcium chloride (available in most lawn and garden centers).

Sunscald: This appears first as a yellowish, discolored spot on top of a tomato, and then eventually it turns about as ugly as a bad case of blossom end rot. True to its name, the cause of this blemish is ol’ Sol. Too much sun is the culprit here. This disorder usually happens to tomatoes that ripen on the upper branches of plants. With less shade from the sun, these fruits easily become overexposed to the harsh summer rays. However, practicing conservative pruning that doesn’t include any of the shade-making top branches, or using a light covering such as cheesecloth, will keep the damaging sun off your ripening beauties.

Cracking: Concentric — and disfiguring — rings that surround either the stem or blossom ends of tomatoes mark this condition. It is caused by the fruits growing too rapidly and literally expanding out of their skins. This problem usually occurs when it rains after a long dry spell. Too much water too soon becomes too much of a good thing, and it causes the tomatoes to crack. Mulching the plants will help steady the moisture supply, and a regular watering schedule when the rains don’t come will prevent this disorder as well. If this seems to be a persistent problem in your garden, there are also varieties available that are resistant to cracking.

Catfacing: Have any disfigured or deeply scarred tomatoes? They were probably the victims of catfacing. Don’t take the name of this problem too literally by thinking rogue cats are the cause of the problem. No, “catfacing” is just a term used to illustrate the disorder. With a lot of imagination, you can sometimes see cat faces formed by the disfigurements. This problem begins early in the development of a tomato fruit. While some sucking insects can cause it, cool weather is usually the culprit. Chilly temperatures can cause abnormal pinches, wrinkles, and creases in young fruit, which magnify as the tomatoes grow bigger. Early spring plantings are usually most susceptible to this ailment. So, if your first few tomatoes show signs of catfacing, don’t worry; any fruit that follows should be free of this disorder unless June and July are much cooler than normal — and when was the last time that happened in our state?

For 20 years, L.A. Jackson contributed gardening stories and tips to Our State magazine. These tips are taken from the Tar Heel Gardening archives, and first appeared in the June 2003 issue of Our State.

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Since 1933, Our State has shared stories about North Carolina with readers both in state and around the world. We celebrate the people and places that make this state great. From the mountains to the coast, we feature North Carolina travel, history, food, and beautiful scenic photography.

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