Common tomato questions
It is that time of year when it seems that everyone is having problems with their tomatoes. Here are a few commonly asked questions that I get at the office. I hope this helps.
Q. My tomato plants look great. They are dark green, vigorous and healthy. However, flowers are not forming any fruit. What is the problem?
A. Several conditions can cause tomatoes to not set fruit. Too much nitrogen fertilizer, nighttime temperatures over 70 degrees F., low temperatures below 50 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. If Extension recommended varieties are used, the main reason tomato plants do not set fruit is because they are not planted where they can receive 8 to 10 hours of direct sunlight daily. Any less direct sunlight will result in a spindly growing, nonproductive plant with healthy foliage.
Q. What causes a tomato to crack? Is there anything I can do to prevent it?
A. 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. This is especially important when the fruits are maturing. Some varieties are resistant to cracking, but their skin is tougher.
Q. About the time my tomatoes ripen and turn red, I lose at least half my crop to bird damage. What can prevent this?
A. Bird damage is common in all areas. One control method which works quite well is to take old nylon stockings and cut them into pieces 10 to 12 inches long. Tie a knot in one end of the stocking and slip the open end over the entire cluster of tomatoes. Secure the end above the tomato cluster with a rubber band or twist-tie. Birds will not be able to peck through the nylon. Slip the stocking off the cluster and harvest the ripe fruit and replace it to protect later-ripening fruit. Also, birds damage fully mature fruit more readily than breaker or pink fruit. Harvest in breaker or green-wrap stage. Gardeners have tried many ways to reduce bird damage. Scarecrows, aluminum strips, tin foil plates and noisemakers will work until the local birds become accustomed to seeing or hearing them. Fabric covering materials such as Grow-Web and Reemay can also be used as a barrier mechanism.
Q. What causes tomato leaves to curl?
A. 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.
Your garden and landscape questions are always welcome. You may either contact me at our County Extension office, 940-716-8610, or by e-mail, firstname.lastname@example.org. You are always encouraged to visit the Wichita County Master Gardener website at www.overthegardengate.org. Another great website to visit for very useful garden hints and answers is http://aggie-horticulture.tamu.edu/. This article, along with every article, will also be featured on www.joetomwhite.com 24 hours a day under county agents.