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TTU News

Cookeville, Tenn. (April 23, 2009) – Although spring is already here, a group of local farmers and educators are trying to make the growing season come even earlier by learning special season-extending growing techniques.
To do that, the group recently took a farm tour, hosted by Paul Wiediger of Au Naturel Farms in Bowling Green, Kentucky, to learn about season extension for fruits and vegetables through the use of techniques like high tunnels, which not only can allow farmers to grow produce throughout the year but can also increase sales potential in local markets.
The farmers and educators who joined in the tour are part of a group working on a $100,000 Cooperative State Research, Education, and Extension Service, United States Department of Agriculture Grant, which was funded by the Agricultural Prosperity for Small- and Medium-Sized Farms program led by S. Sureshwaran, Ph.D., in Washington, D.C.
“Through the College of Agriculture and Human Ecology, projects like this one are showing that Tennessee Technological University is gradually becoming an organic research center,” said Dennis George, director of the Center for the Management, Utilization and Protection of Water Resources, the research center through which the grants are run.
“If farmers can utilize organic techniques to build soil quality, this will help improve the yields of the farmers and also reduce runoff and improve water quality in the streams and rivers,” said Kim Stearman, professor of soil science and co-project investigator.
According to Michael Best, associate professor of agricultural economics and project director, a major goal of the project is to develop educational programs to get farmers involved in high-tunnel techniques.
High tunnels are not conventional greenhouses because, unlike in greenhouses, crops are planted directly in the soil. But like plastic-covered greenhouses, high tunnels are generally Quonset-shaped, which means they are constructed of metal bows attached to metal or wooden posts driven into the ground. High tunnels are covered with greenhouse-grade polyethylene and are ventilated by manually opening the doors from either end or by manually rolling up the sides each morning and rolling them down in early evening, depending on temperature. There is typically no permanent heating system although some growers have a standby portable propane unit to protect against unexpected cold temperatures. There are no electrical connections, with the only external connection being for water, usually applied by drip irrigation.
On the Wiedigers Au Naturel Farms, high tunnels have been used for year-round growing for more than eight years. Red leaf and Romaine lettuce, green leaf lettuce, and spinach and baby greens, including mizuna, red kale, and arugula are grown from
November through April. Their high tunnels are unheated. The farm’s Web site ( documents what happens to lettuce when the temperature in the high tunnel goes below freezing. The lettuce can actually have ice on it but recovers as temperatures rise in the high tunnel.
For decades, the agricultural industry had been moving toward growing foods where there was a comparative advantage to do so and then shipping them to the consumption centers. Technological advancements in processing and cooling preservation and low transportation costs made that possible.
“But now, the industry seems to be moving back somewhat toward more localized food production, which could boost the profitability and sustainability of the small- and medium-sized farms that are so abundant in Tennessee,” Best said. “This trend may be attributed to the high fuel prices of last year, environmental concerns over fuel used for shipping, and more recently, the health concerns associated with the safety of products that are produced on large-scale farms in distant states and countries.”
National discussion about the local food movement has increased recently, due to quality and local economy issues and, now, transport costs. A new term, “locavore,” has
even been coined to describe someone who prefers to eat locally produced food. The effect of increased shipping costs on the cost of food will be critical to the movement. With low-cost technologies like high tunnels and growing in close proximity to large
population centers, small- and medium-sized farms will offer a solution for those consumers who prefer to eat locally.
To further the movement, Best and Stearman intend to work alongside local farmers to help them increase production and develop better methods for reaching the area public who are simply unaware of the availability of local produce.
“This industry [organic farming] is growing fast,” Stearman said. “For the last 10 years, it’s been growing at 20 percent per year. It’s important for us to get involved in this field of research, and we appreciate the support that the Water Center and College of Agriculture and Life Sciences have provided already.
“We are fortunate to have the Waters Farm that utilizes organic farming techniques under the guidance of horticulturist Randy Dodson.”
There is also a high school educational component of the project that is being prepared by Ben Byler, professor of agricultural education. He is organizing a group of regional high school teachers that will meet on the TTU campus to help plan new teaching modules. It will be determined how teachers will teach these new production
methods and what tools they will need to do so. With the high school teachers’ input, Byler will oversee the development of a sample DVD instructional module, which would
contain one module of what would be 10 or 12 potentially. This module will then be
used by the teachers to make additional refinements and to test it on their high school classes.
In the past few years, there has been a tremendous amount of interest in local markets for fresh produce. According to Cheryl Brown, in a 2003 study of southeast Missouri, the most important attributes of produce were quality and freshness, and most consumers perceived the produce at local farmers’ markets to be of a higher quality and lower price. This is not always the case. At many markets, when crops are in season and at their peak quality, farmers are able to charge a higher price than the supermarkets charge for the same product. This relates to the perceived quality difference in those products, which means that, to the consumer, they are not the same product. Results from studies like these show that knowing where your food is coming from, how it’s produced, and the quality of the product is more important to the consumer than socio-economic, geographic, or environmental and health factors.
“As interest grows in these types of production methods, there will be a need for the development of markets for the produce,” Best said. “With Tennessee’s climate, farmers have the potential to extend the current growing season dramatically with these innovative production techniques, and extending the growing season makes local marketing channels a more viable option.”