If you have tomatoes growing in your garden, chances are good you have at least one of these problems.
1. Failure to set fruit. Every year gardeners have tomatoes that flower but do not set fruit.
This is caused by low night air and soil temperatures (below 55 degrees), abnormally hot weather, low soil moisture, excessive shading or over fertilizing. In most cases the problem will correct itself.
2. Blossom end rot. This disorder causes the fruit to have a dark sunken area on the blossom end. This can be prevented by maintaining good, even soil moisture at all times. Excessive moisture (wet feet) for an extended period can also be as damaging as lack of moisture. Damage to roots caused by hand cultivation can also affect uptake and movement of calcium - a possible cause of this disorder.
Mulches are helpful for their ability to moderate soil moisture fluctuations, as well as to eliminate the need for cultivation. Improper pH can prevent the plant from absorbing enough calcium.
3. Mosaic diseases. There are several viruses that will produce mottling and curling of leaves and disfiguration of fruit on tomatoes.
These diseases are spread by insects, animals and humans. Aphids are the chief insect vectors and should be controlled by using insecticides. Animals and humans can also carry this disease from one plant to another.
Do not allow anyone to smoke in your garden.
Smokers should always wash their hands before touching the plants. Tobacco Mosaic Virus can be spread from an infected cigarette to your tomatoes as well as your cucumbers, squashes, asters, roses and many other plants.
4. Wilt. Both Fusarium and Verticillium can cause early dying of tomatoes.
The diseases cause the plant to wilt even with good moisture.
If you cut the stem of the plant the vascular or conducting tissue will be discolored. Both wilts are soil born and widespread throughout the South.
They also infect potatoes, peppers, eggplant, melons and many other vegetables and some ornamentals. The only solution is to use resistant varieties.
5. Leaf roll. This disorder is characterized by upward rolling of tomato leaflets on older leaves. Leaf roll has been associated with varieties having specific gene (wilty gene); symptoms usually are seen when plants have a heavy fruit load.
Environmental factors reported to promote symptoms include high temperature, drought and prolonged periods of wet soil conditions.
6. Blights and other fungus diseases. There are a number of fungi that are important on tomatoes.
Most of these can be controlled by regular sprays of recommended fungicides. For early and late blights, anthracnose and fruit rots, use a fungicide once each week when the disease first appears.
7. Herbicide Injury. Hormone type herbicides such as 2, 4-D, Banvel D, etc. used near the garden can cause serious damage on tomatoes. The symptoms are downward curling leaves and twisting new growth.
Symptoms are similar to many of the common virus diseases. Do not spray these materials on a windy day or near the vegetable garden.
Don't use grass clippings for a mulch or in a compost pile if the lawn was recently treated with a herbicide.
8. Aphids. Plant lice cause a loss of plant vigor and may carry disease. There are many chemical preparations for controlling aphids; read and follow label directions. Insecticidal soap is an organic spray that controls many soft bodied insects.
9. White Fly. White fly has become a major problem in tomatoes. Many times when you touch a plant there will be just a cloud of white rising up. They feed on the plant causing weak growth.
10. Tomato Hornworm. Large green worm with a horn on the backend. Hand-pick these large insects from small plantings, but be careful because the hornworm has a bad sting.
Tomatoes can give you a great deal of satisfaction in your vegetable garden.
They are not very difficult to grow if you are willing to put in the necessary time and effort.
One other reminder: This year's Dawson County Produce Market continues to be great.
The market opens each Wednesday and Saturday by 7 a.m. and ends when sellers are sold out.
The market is located in the Dawson County Agricultural Service Center parking lot on Academy Avenue.
For more information, call the extension office at (706) 265-2442.
Clark Beusse is the Dawson County extension agent. For more information, call (706)265-2442.