Agronomic Services — News ReleaseFOR IMMEDIATE RELEASE
MONDAY, NOV. 8, 2010
Contact: J. Kent Messick, Field Services Section chief
NCDA&CS Agronomic Division
NCDA&CS services helped Calahaln Vineyards correct soil nutrient issue, saving plants and improving production
MOCKSVILLE—Cathy Powell loves the outdoors and grew up on a farm, but she never imagined that she would one day run her own vineyard. Her journey down this road began six years ago when she tried to save an especially cherished grape vine on her family property. One thing led to another, and now she has acres of grapes—red and white muscadines as well as the hybrid Cynthiana/Norton, grown by Thomas Jefferson and known as the “cabernet of the Ozarks.”
Powell’s adventure began in 2004 when she visited a local vineyard on a fact-finding mission. The purpose of her trip was to get advice on how she could save a large grapevine after the tree supporting it had died. She found herself awed by the beauty of the vineyard’s meticulously manicured fields.
The next week, Powell’s husband attended a meeting in Dobson and heard about Surry Community College’s viticulture program. He recognized it as an opportunity his wife would appreciate.
“The following Monday, I was in class, and it was not a beginner class,” Cathy Powell said. “That is what happens when your husband thinks you are superwoman. I was overwhelmed and unfamiliar with the terminology, but I studied hard, got hands-on training working in local vineyards and enjoyed myself thoroughly.”
The Powells began serious preparations for a vineyard in the fall of 2005: clearing land, taking soil samples, and researching varieties, trellises, fertilizers and equipment. By the spring of 2006, they had planted six acres of muscadine grapes — four acres of the red variety Noble and two acres of the white variety Carlos. In addition, Powell planted two acres of the Cynthiana/Norton grapes she had heard about in class. These hybrid grapes of uncertain origin were in cultivation in the eastern United States by the early 1800s.
Powell chose carefully and purposely. She wanted grapes that had minimal pest problems and desirable attributes such as high levels of antioxidants, including the heart-healthy compound resveratrol. She also wanted there to be slight differences in maturity times so she could stagger timing of routine maintenance. Those prerequisites contribute to the efficiency of the operation.
In her determination to do things right, Powell researches each step she takes thoroughly and seeks expert advice. Early in the process, however, one recommendation almost brought her enterprise to a halt. That piece of advice involved application of the fertilizer boron.
Boron is a micronutrient. Grapes need it but only in very small quantities. The recommendation she received and followed was way too high. Within days, her Noble and Cynthiana/Norton plants shriveled.
“I about panicked when I saw the cupped, burnt foliage,” she said. “After you put that much work in a vineyard, . . . seeing that kind of damage . . . you about have a stroke.”
Powell summoned Cooperative Extension agent Colleen Church to help troubleshoot the problem. Church took photos and collected plant tissue samples for nutrient analysis. When tests confirmed that boron was present in toxic amounts, Church suggested Powell contact regional agronomist J. Ben Knox with the N.C. Department of Agriculture and Consumer Services. She knew that he was more familiar with grapes and that crop nutrition was his particular area of expertise.
When Knox visited, saw the plants and looked at the report results, he was astounded by the high levels of boron.
“Lowering levels of boron is possible,” Knox said. “I’d just never seen a situation where they needed to be lowered so much.”
After consulting with fellow agronomist Bill Yarborough, Knox suggested that Powell water the vineyard heavily to move as much boron as possible out of the root zone. Then he advised her to apply calcium through the drip irrigation system to raise the soil pH. As soil pH increases, boron becomes chemically tied up, reducing its availability to plants.
Knox and Powell continued to monitor the problem by collecting and submitting plant tissue regularly. It took several months to see improvement, but by the next year, the plants had begun to recover. They had slightly less foliage and produced fewer grapes than the ones that had not received extra boron, but they were alive and regaining vigor.
“Dealing with this problem helped the Powells identify and address other nutrient issues,” Knox said. “Using tissue reports, I explained the importance of potassium in particular. After increasing this nutrient, Powell saw a noticeable increase in the size of the grapes.”
Powell has continued to use agronomic testing services and solicit Knox’s input. She submits soil and tissue samples when she notices vines ripening unevenly and then applies spot treatments of lime and fertilizer based on report recommendations. Ripening has become much more uniform.
It takes several years for grape vines to become established, and Powell’s vines are just now maturing to the point where they can be harvested. They produced three tons of fruit this year. The Cynthiana/Norton variety is going to the Wolfe and Silk Hope wineries. Powell is excited about this arrangement since Silk Hope Winery is a recent Silver Medal winner in the 2010 Mid-Atlantic Southeast Wine Competition for its Haw River Norton 2008 vintage.
Powell feels like she has reached an important milestone and is grateful for the assistance she received in getting there. She looks forward to getting established and reaching the point where she can make her own wine.
“It is so important to have an adviser to rely on because there’re always going to be little things that come up,” Powell said. “I think Ben’s a knight in shining armor. Without his advice and the agronomic testing services, I probably would have lost my grapes.”
The NCDA&CS Agronomic Division has 13 regional agronomists who can make on-site visits, evaluate suspected nutrient problems and give advice on collecting and submitting agronomic samples, understanding test results, liming, fertilization, composting, irrigation and nematode management. To contact theagronomist assigned to your area, visit www.ncagr.gov/agronomi/rahome.htm.