Consider this before growing tomatoes

Gardening is the No. 1 hobby in America, and growing vegetables is a large part of gardening. Tomatoes are one of the most popular crops.

//

There is nothing better in the summer than going out and picking a vine-ripe tomato and eating it. The tomato is so popular there is even a song written about it. If you have never heard the tomato song, you can attend the tomato class next March that is sponsored by the Vocation Agriculture Teachers in Columbia County and hear Chuck Anderson, retired agriculture teacher at Evans High School, sing the tomato song.

Tomatoes are easy to grow, but there are some problems gardeners should consider. Most of these problems are disease related, but some are about nutrient deficiencies.

As a gardener, you can help reduce disease problems by following a few simple rules. The first rule is to buy disease-resistant plants. The letters behind a tomato variety's name tell what diseases it is resistant to -- T-Tobacco Mosaic Virus, V-Verticillium Wilt, F-Fusarium Wilt and N-Nematodes. However, resistance does not mean the plants are immune to these diseases.

The second rule is to practice rotational planting. Move tomatoes away from where tomatoes, potatoes, eggplant or peppers were planted last year. Soils in these areas might harbor leftover diseases. Bury all plant debris at least 6 inches when tilling to keep the disease organisms away from the plants.

Even buying disease-resitant plants and incorporating a rotational planting method doesn't mean that the tomatoes are safe.

The number one tomato disease now is Tomato Spotted Wilt Virus (TSWV). Most viruses that cause disease problems are spread by insects, including aphids, whiteflies, plant hoppers or thrips. TSWV is spread by thrips. The symptoms are the top of the plant will look stunted or wilted, and the young leaves might turn yellow and often have brown or black discoloration in them. The veins on the underside of leaves might thicken and turn purple. The fruit can have circles on them that are raised or flat. Ripe fruit will have yellow circles or semicircles. The stem might have long brown lesions.

Once tomatoes get the disease, there is no control.

There are two varieties of tomato that are resistant to TSWV. I grew them in my garden last summer for the first time and had good success with them. The skin of these tomatoes is a little thicker than other varieties. The flavor is good and is best if you leave them on the plant as long as possible.

If you have plants that are showing signs of TSWV, you need to destroy infected plants as quickly as possible early in the season to prevent spreading the thrips. You need to seal them up in a plastic bag. Even after the plant is pulled up, thrips can leave the plant to spread the virus. Late in the season you might just want to let the infected plants finish ripening the fruit they have. Late season infection is less of a concern.

The next problem that I am getting some calls on is bacterial wilt. Bacterial wilt causes a rapid wilting and death of the plant. The plant dies so quickly it does not have time to yellow. Most callers say that the plant looked good one day and looked like someone poured boiling water on it the next.

An easy way to identify bacterial wilt is to cut through the stem of the tomato and look at the center of the stem. Bacteria wilt browns the pith or middle of the stem. On bad infections, the pith might be hollow.

Unfortunately, there are no controls or resistant varieties for bacterial wilt. If you have this problem in your garden, carefully dig out infected plants and soil and discard. Make sure that the discarded soil is not in an area you will use to plant vegetables in the future. Next, clean your tools with alcohol or a chlorine mix. Don't plant any vegetables in that area for at least four years.

Another concern of tomato growers is rolling of the plants leaves.

Leafrolling occurs when the plant has a heavy load of fruit and the light intensity is high.

The condition is harmless and should not hurt final production. However, there is a virus that can cause this problem. The only way to tell if this is a virus is to look at the fruit. The fruit will be misshapen or have dark spots on it.

Columbia County Extension Agent Charles Phillips can be reached at (706) 868-3413 or by e-mail at charlesp@uga.edu. The Extension Web address is www.ugaextension.com/columbia.