Are you having tomato problems?

Staff Writer
Brownwood Bulletin
Scott Anderson

My tomato plants look great. They are dark green, vigorous and healthy. However, flowers are not forming any fruit. What is the problem?

Several conditions can cause tomatoes to not set fruit. Too much nitrogen fertilizer, nighttime temperatures over 75 degrees F., irregular watering, insects such as thrips or planting the wrong variety may result in poor fruit set. Any of these conditions can cause poor fruit set, but combinations can cause failures. Another reason tomato plants do not set fruit is because they are not planted where they can receive 8-10 hours of direct sunlight daily. Any less direct sunlight will result in a spindly growing, nonproductive plant with healthy foliage.

Are there really low-acid tomato varieties?

There are some varieties that are slightly less acidic than others, but this difference is so slight that there is no real difference in taste or in how the tomatoes should be processed. Some yellow-fruited types are slightly less acidic than the normal red varieties, but not enough to make any difference. Research conducted by the USDA indicates that all varieties available to the home gardener are safe for water bath processing as long as good quality fruit are used. Flavor differences which exist between varieties are not because of differences in acid content, but balances of the sugar to acid ratio.

Can I save seeds from my tomatoes from next season's plantings, and if so how?

You can save seed from tomatoes if the variety is not a hybrid. Hybrid tomatoes do not come true from seed. The plants and fruit from seed saved form your home garden may or may not resemble the parent. Chances are the fruit will be poorer quality and the vine characteristics will not be the same as the parent plant. However, for true breeding varieties, such as Homestead, it is easy to save seed. To save seed from tomatoes or any other home vegetable fruit crop, leave the fruit on the plant until it is mature, pull it, squeeze juice with seed into a glass, let this ferment for two days adding water if needed. Rinse the seeds two or three times to remove debris. Seeds will settle to the bottom. After rinsing the seeds, blot them and place them in the sun to dry. Store the seeds under cool, dry conditions.

What causes a tomato to crack? Is there anything I can do to prevent it?

Cracking is a physiological disorder caused by soil moisture fluctuations. When the tomato reaches the mature green stage and the water supply to the plant is reduced or cut off, the tomato will begin to ripen. At this time a cellophane-like wrapper around the outer surface of the tomato becomes thicker and more rigid to protect the tomato during and after harvest. If the water supply is restored after ripening begins, the plant will resume translocation of nutrients and moisture into the fruit. This will cause the fruit to enlarge; which in turn splits the wrapper around the fruit and results in cracking. The single best control for cracking is a constant and regular water supply. Apply a layer of organic mulch to the base of the plant. This serves as a buffer and prevents soil moisture fluctuation. Water plants thoroughly every week. This is especially important when the fruits are maturing. Some varieties are resistant to cracking, but their skin is tougher.

What causes the black spots on the bottom of my tomatoes?

Blossom end rot caused by improper (fluctuating from too dry to too moist) moisture. Maintain uniform soil moisture as the fruit nears maturity. Remove affected fruit

What causes tomato leaves to curl?

The exact cause of tomato leaf roll is not fully known. Tomato leaf roll appears about the time of fruit setting. The leaflets of the older leaves on the lower half of the tomato plant roll upward. This gives the leaflets a cupped appearance with sometimes even the margins touching or overlapping. The overall growth of the plant does not seem to be greatly affected and yields are normal. This condition appears to be most common on staked and pruned plants. It occurs when excessive rainfall or overwatering keeps the soil too wet for too long. It is also related to intensive sunlight which causes carbohydrates to accumulate in the leaves. Some varieties of tomatoes are characteristically curled.

Do products which are supposed to aid in setting tomatoes really work and if they do, how should they be used?

These hormonal products are designed to substitute for natural pollination. These products work better when tomatoes are failing to set because of too cool temperatures. Tomatoes which set after use of these products will be puffy and have less seed.

Should you allow tomatoes to become fully ripe and red on the vine before harvesting?

Generally, yields will be increased by harvesting the fruit at first blush or pink instead of leaving them on the plant to ripen fully. A tomato picked at first sign of color and ripened at room temperature will be just as tasty as one left to fully mature on the vine. Picking tomatoes before they turn red reduces damage from birds.

I have large translucent areas on my tomato fruit. What's going on?

This is an environmental problem. The translucent areas are sun scalds. Heat from direct intense sunlight destroys the color pigments of the tomato. This damage does not make the tomato inedible.

Is a tomato a fruit or a vegetable?

The tomato is legally-declared a vegetable by the Supreme Court of the United States. A vegetable is an herbaceous (non-woody) plant or plant part which can be eaten without processing and is usually consumed with the main meal.

What do the letters "VFN" associated with particular tomato varieties indicate?

VFN indicates the tomato variety is resistant to three types of diseases; Verticilum wilt, Fusarium wilt and nematodes. Many of the new hybrid varieties are VFN types. Disease resistant varieties preferred in areas of Texas where these problems are severe and cause great losses to home gardeners.

Disease resistance in tomatoes indicated by initials include:

V - Verticillium wilt

F - Fusarium wilt (F1, race 1; F2, race 2)

N - nematode

T - tobacco mosaic virus

A - Alternaria alternata (crown wilt disease)

L - Septoria leafspot

Garlic can help with fly control

Canadian research project showed garlic might reduce fly populations by 50%.

Fly control is always a hot topic as the summer progresses, and chemical controls may work but also may have negative effects on desirable species like dung beetle.

One option to help is feeding garlic through mineral or salt, but until recently there appeared to be little or no research to support the practice. It was based on speculation and observational supposition.

However, in 2017, researchers in Saskatchewan actually measured positive effects of feeding garlic powder in a salt-trace-mineral mixture upon fly numbers on cattle. They incorporated garlic powder at 2.1% of the weight of the salt-trace-mineral blend and found a reasonable level of fly control.

The Canadian researchers used three cow-calf herds, each in a different pasture about 3 kilometers apart, from May 25 to Sept. 13. Two herds got only the salt-mineral mix and the other got the garlic in that mix.

The researchers said the group eating the garlic blend consistently had the lowest fly count and exhibited the least fly-avoidance behavior throughout the trial period. Fly counts done with pictures and a program that counted flies showed a season-long average was 75 flies per cow for those in the garlic herd. The cows in the two control groups that received salt-mineral mix only had average fly counts of 156 and 171.

Daily consumption of the garlic blend was 0.12 pounds of the mix each, including cows, calves and bulls. Salt-mineral consumption was 0.18 pounds and per head per day for control group No. 1 and 0.15 pounds for control group No. 2.

Equally important, the cost looked advantageous. Garlic for the grazing season cost $1.46 per head, while two recommended doses of a chemical control would have cost $2.12 per head.

Apparently, the garlic research at Lakeland College in Saskatchewan is ongoing.

A surprising number of mineral dealers these days offer products that include garlic.

In addition to potential fly control benefits, garlic is sometimes claimed to aid digestion, improve gut health and offer anti-microbial properties. Similar claims are made for cinnamon and cayenne pepper, so these things are also being fed to cattle and included in mineral mixes and other supplemental products.