Don't buy tomatoes in the grocery store when you can grow tomato plants in your own backyard. Whether they are the vining or bush variety, tomato plants produce a bountiful harvest of fruit that's rich in both nutrients and flavor. Though they're relatively low maintenance, some tomato plants may succumb to various insect pests or disease problems. Immediate treatment is necessary to prevent widespread plant loss.
Tomatoes need lots of water. A non-fruiting tomato plant should get approximately 64 oz. of water a day, according to the University of Missouri. Once it starts producing fruit, the plant should receive approximately 128 oz. of water per day day. Plants that don't receive adequate water will appear wilted or have yellow leaves, and any fruit on the plant may appear shriveled or stunted.
Tomatoes are sensitive to the sun, even though the plant itself requires full sun for proper development. Excessive pruning will expose the ripening fruit to too much sunlight, causing scar-like yellow or white patches on the tomato fruit.
Tomato hornworms may be small--the caterpillars only measure 3 to 4 inches--but they can devour much of a tomato plant's foliage if left untreated. Manual removal will quickly eliminate the problem. For widespread control, such as in large tomato gardens, a commercial insecticide formulated with carbaryl will effectively kill them. Other common insect pests include beetles and aphids, which can be controlled with a standard insecticidal soap.
Tomato Mosaic Virus
Many tomato farmers and backyard gardeners fear the tomato mosaic virus, and with good cause. As of March 2010, there is no adequate chemical control. The best option for a tomato afflicted with the virus is compete removal to prevent the virus from spreading to new plants. Symptoms include mottled yellow-and-green coloring on the tomato plant's leaves. Gardeners can minimize the risks of contacting the virus by growing tomato plant varieties that have been specifically bred to be resistant to the disease. These are denoted with a "T" at the end of their name, such as Suncherry (T) and Golden Cherry (T).