There are several accounts that Thomas Jefferson struck fear into the hearts of dinner guests and crowds in Virginia by eating a tomato. While eating a tomato is extremely commonplace now and not exactly shocking by today’s standards, it was believed during the late 18th century that tomatoes were toxic. Tomatoes are in the Solanaceae family that does include species that contain toxic alkaloids, but tomatoes do not have those properties.
Therefore, it must have been shocking to think that Thomas Jefferson was publicly poisoning himself. While tomatoes are obviously not poisonous, they are susceptible to a lot of issues. In fact, “what’s wrong with my tomatoes?” is probably the most popular question I get asked per year. There are cultural issues that can affect all vegetables, but the problems described below are fairly specific to tomatoes. There are also a few diseases to be on the look out for.
Sunscald can look like a disease, but it is where the fruit looks brown, wrinkled, and sunken. This problem happens when the fruit is exposed to the sun for an extended amount of time. Blossom-end rot is where the bottom end of the fruit is black and water-soaked in a round or circular shape. It is caused by a calcium deficiency.
Cat-facing presents itself as malformed fruit with greenish bands. This is usually caused by inconsistent irrigation, poorly drained soils, or the plants were planted too early. Fruit cracking will typically appear closer to the stem in either circular or radial cracks. It is caused by inconsistent irrigation. What usually happens is that the plants do not receive water or enough water for a period of time and then gets way too much. Each of these issues are cultural and can be prevented or managed fairly easily.
There are also a few diseases that will affect your tomatoes as well. Early blight is Alternaria that produces brown lesions on the leaves, stems and fruit. It will be more active during warm and wet weather. Management methods include removing infected plant material and using fungicides if necessary. Late blight is Phytophthora that causes similar symptoms as Early blight. Management methods are the same as Early blight. Tomato spotted wilt virus (TSWV) displays itself as bronzing of the upper sides of younger leaves and develop brown spots that look like concentric rings. Fruit will have chlorotic spots or blotches and concentric rings.
TSWV is vectored by thrips; therefore, controlling thrips will prevent infection. If you have this virus then it is best to remove the plant Plants with Fusarium wilt will yellow, wilt and die. Once death occurs the plant needs to be removed.
If you see any problems with your tomatoes feel free to bring a sample by the Extension office or email a picture.
As always, if you have any questions with horticultural or other agricultural related topics stop by the Extension office, call 478-986-3958 or email brennan4@uga. edu.
