By Johnny Jackson
Tomatoes are ripening and the phone is ringing with concerned gardeners wanting to know what strange disease is attacking their plants, said Frank Hancock, agriculture and natural resource extension agent in Henry County.
"This time of year, people just line up bringing their leaves off their plants to tell us what's wrong with them," Hancock said. "But, of all the summer growing, tomatoes generate the most phone calls."
Hancock said a great many area residents have been experiencing what is called "Blossom End Rot."
"Blossom End Rot is not a disease, but is a physiological problem associated with the lack of calcium in the developing plant," he said. "It is a calcium deficiency [that] starts in the soil."
Tomato plants may not blossom due to the rot. Conditions that contribute to this problem include dry soil that won't permit calcium to be dissolved into the plant's roots, or too-wet conditions, in which roots do not function normally.
"Tomatoes need about 1.5 inches of water per week," Hancock said.
He advises that growers can prevent the rot by watering the roots instead of the foliage. Growers should also plant tomatoes in well-drained areas and use mulch to maintain uniform moisture levels. Soaker hoses are best to water tomato plants when it is not raining.
Calcium deficiency can be discovered by soil testing and corrected by adding Dolomitic limestone or other calcium sources to the soil. Limestone takes a while to work, Hancock said, so this needs to be done in the fall or very early spring.
Sandy Foster said she has heard of several different home remedies, from crushing egg shells on the ground, to using calcium-rich powdered milk. Foster admitted, however, that she is yet a novice gardener. The Clayton County family and consumer science county agent is still waiting to see the return on her own tomato garden.
For all gardeners, it is important to test the soil, Hancock said. "Tomatoes like a soil Ph of 6.2 to 6.8. The Ph of your soil will also be determined by the soil test," he said. "If the Ph is too low, the plant cannot use the calcium that may be available in the soil and, therefore, shows symptoms of calcium deficiency even though levels seem to be high enough."
Tomatoes do not require much fertilizer. Growers are advised to put down about one and a half pounds of a complete fertilizer (10-10-10 per hundred feet of row) prior to planting. Apply another row of fertilizer when the fruit first forms. It can be repeated every three to four weeks, while the plant is producing. Growers should not use ammonium nitrate, Miracle Gro or any other fertilizers that are high in nitrogen.
"There are Blossom End Rot sprays that contain things like calcium chloride, which can be of some help," Hancock said. "Spray them on the foliage and not on the tomatoes. The foliage can take in some calcium, but the fruit does not. Blossom End Rot sprays will not help the tomatoes already affected, but it can help the future crop."
Hancock said that tomato plants are easier to grow than they seem. "Sometimes, we take such good care of it, we drown them with too much water and fertilizer," he said.
The extension offices of Henry and Clayton counties host various classes throughout the year on plant growing, gardening, and conservation.
Sandy Foster will host a "Preserving Summer" preserves seminar today, from 12:15 - 1 p.m., at the Clayton County extension office, located at 1226 Government Circle in Jonesboro. The extension office also plans to host its second community farmer's market this Saturday from 8 a.m. - noon at the office. For more, call the Clayton County office at (770) 473-3945.