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Common Problems Insects: Tomato hornworms are large (two to three inches long when fully grown), green worms with white stripes on their bodies. A horn protrudes from the top, rear end of the worm. Tomato hornworms feed on the leaves and fruit, and several worms on one plant can quickly defoliate it. They are difficult to see when small. Hand pick the worms or use a suggested biological insecticide. Tomato fruit worms are almost sure to be found in the garden. The moth lays the eggs in the terminal (top growth of the plant), then the larvae (small worms) hatch and make their way to the fruit. Once the larva is inside the fruit, it's too late to save that fruit. Use the recommended insecticide every seven days. Diseases: Verticillium and fusarium wilt are seedborne diseases that cause yellowing of the leaves, wilting, and premature dying of the plant. These diseases will persist in gardens where susceptible plants are grown. Once they build up, the only practical control is the use of resistant (VF) varieties. Early blight is characterized by dead brown spots that usually start on the lower leaves and spread up the plant. Upon close inspection, you can see concentric rings within the spots. Although early blight is most severe on the leaves, it sometimes occurs on the stems; it can cause defoliation. You may need to use fungicide sprays to achieve high yields and quality fruit. Some varieties are more tolerant of early blight than others. Remove diseased leaves from the garden and dispose of them. Septoria leafspot is characterized by numerous small black spots on the leaves. The center of these spots later turn white, and tiny black dots appear in the white center. The disease starts on the bottom leaves and may become severe in wet weather. Use suggested fungicides for control. Physiological disorders: Blossom-end rot, a dry, leathery rot of the blossom end of the fruit, is common in home-grown tomatoes. It is caused by a combination of calcium deficiency with wide fluctuations in soil moisture. Severe pruning causes stress to the plants that increases the incidence of blossom-end rot. Some tomatoes are much more susceptible to this condition than others. Mulching and uniform watering will help prevent blossom-end rot. Poor color and sunscald occur when high temperatures retard the development of full red color in tomatoes exposed directly to the sun. Sunscald appears on the fruit during hot, dry weather as a large, whitish area. It becomes a problem when foliage has been lost through other diseases, such as early blight. Diseases: early blight, septoria leafspot, verticillium and fusarium wilts, late blight, tobacco mosaic virus, bacterial spot, tomato spotted wilt virus. Insects: flea beetle, hornworm, stink bugs, Colorado potato beetle, fruitworm, aphids, mites, whiteflies, cutworms Other Pests: nematodes Cultural: blossom-end rot, irregular soil moisture or calcium deficiency; poor color, yellow spots or large whitish-grey spots, sunscald from lack of foliage cover; leaf roll; fruit cracking, irregular soil moisture; Black Walnut wilt, caused by roots of tomato plants coming in contact with roots of black walnut trees
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