Jeff Kuehny, Hanna, Hanna Y., Sanderlin, Randy S., Hall, Michael J., Coolman, Denise | 4/23/2005 12:19:05 AM
BOSSIER CITY – Greenhouse tomato growers looking for alternative crops to grow when they don’t have tomatoes in their greenhouses could consider poinsettias, according to LSU AgCenter experts and growers.
Those comments came during the LSU AgCenter’s 8th Annual Greenhouse Tomato Seminar Feb. 27 at its Red River Research Station near Bossier City.
Dr. Jeff Kuehny, an LSU AgCenter associate professor of horticulture, said poinsettias can be grown to give growers a little extra cash.
"Poinsettias are grown in the fall when tomatoes are not grown," Kuehny said. "They can be sold to smaller outlets, such as farmers’ markets or local stores."
Doniece and Larry Smith of St. Augustine, Texas, attended this year’s seminar and said they’ve been growing poinsettias as an alternative crop for about 13 years.
"We’ve been extremely successful doing this," Larry Smith said.
His wife agreed.
"We mainly grow (poinsettias) for people in the town," Doniece Smith said. "Shops in the town sell them, and churches and schools buy them to use for decoration during the Christmas holidays. We sell all the tomatoes and poinsettias we raise."
While poinsettias are an ideal alternative crop to greenhouse tomatoes, growers should not grow the two in the same greenhouse at the same time, said Dr. Randy Sanderlin, an LSU AgCenter associate professor of plant pathology. He said that other plants should not be grown in greenhouses when tomatoes are grown and that the greenhouses should be thoroughly cleaned between crops.
"All debris should be removed when cleaning greenhouses," Sanderlin said. "Also, keep the area around greenhouses free from flowering weeds and such."
In addition to cleanliness, air circulation also is important for reducing diseases such as gray mold, he said. The more air that is circulating, the less chance there is for infection. To ensure proper air circulation, make sure plants are not crowded and there is enough space between them for the air to circulate, he said.
"Keep your greenhouses clean," Sanderson said. "Don’t let pathogens build up."
Dr. Mike Hall, an LSU AgCenter associate professor of entomology, said keeping greenhouses free of pests is another important step growers must take when growing greenhouse tomatoes.
"There are a limited number of pesticides that can be used in greenhouses," Hall said. "Therefore, it is important to know what pests are present and an approximate number of pests that are present. This is where scouting comes in."
Growers should scout their greenhouses at least once a week, preferably twice a week, and keep a record of what is found, Hall said. Once an insect is discovered, buy just enough insecticide to last one year, he said.
"This is because the insecticides may break down if they are kept in storage," Hall said. "It is a good idea to check the manufacturing date to see when it was made."
Also during the seminar, Dr. H.Y. Hanna, a professor of horticulture who is conducting a greenhouse tomato research project at the LSU AgCenter’s Red River Research Station, talked about a trip he made to Canada – where he visited greenhouse tomato growers and learned about their production practices. He said the Clarance cluster tomato variety is the variety most grown in Canada.
"Cluster tomatoes are becoming very popular in Canada," Hanna said. "Less labor is needed, and they produce a higher yield. Because of this, they are more economical to grow."
Hanna also warned growers not to grow their greenhouse tomatoes in soil. Perlite is a better medium to use, he said. Perlite is a processed volcanic mineral widely used as a propagating and growing medium for many horticultural crops, including tomatoes.
"If you plant greenhouse tomatoes in soil, sooner or later you’re going to get a bad crop, because of the waste left in the soil from crop to crop," Hanna said. "Perlite can be cleaned, recycled and used over and over."
Greenhouse tomatoes should be grown with no physical contact with the ground, he said.
Growing greenhouse tomatoes may be a venture worth pursuing, Hanna told seminar participants.
The LSU AgCenter researcher predicts the consumption of greenhouse tomatoes will increase as people become aware of the benefits of eating tomatoes. It has been reported that tomatoes contain many nutrients, among them vitamins C and B complex and the minerals iron and potassium, Hanna pointed out.
Also found in tomatoes are carotenoids, including lycopene and beta carotene, which are converted into vitamin A by the human body. Lycopene is believed to have potent antioxidant properties that are thought to neutralize harmful substances in the body that may increase the risk of cancer and cardiovascular disease.
Other topics discussed during the seminar included heating and water sources, as well as pollination practices for growing greenhouse tomatoes.
To find out more about growing greenhouse tomatoes or a variety of other issues ranging from health and nutrition to home lawn and garden care, go to www.lsuagcenter.com.
Jeff Kuehny at (225) 578-2158 or firstname.lastname@example.org
Mike Hall at (318) 797-8034 Ext. 2320 or email@example.com
H.Y. Hanna at (318) 741-7430 Ext. 1116 or firstname.lastname@example.org
Randy Sanderlin at (318) 797-8034 Ext. 2311 or email@example.com
A. Denise Coolman at (318) 644-5865 or firstname.lastname@example.org