Update on Frost Damage on grape vines at the Lane Extension Center
by Warren Anderson
Frost damage on grape vines at the Lane Extension Center
by Warren Anderson
On March 31 The MG vineyard committee planted 16 more Cynthiana/Norton seedlings into the vineyard. On April 14, 2012 Adventures in Agriculture was hosted at the Lane Extension Center. The previous week the vines were frosted. Cynthiana and/or Norton are rated cold hardy if bud break has not occurred. March temperatures in Rutherford County were above normal. Primary buds on the older Norton vines broke and young tender shoots grew. The first week in April, we experienced frost. Upon surveying the vineyard at the extension center on April 14th, I noticed that the new shoots were damaged. Dr. Lockwood, UTK, advised me to wait 2 to 3 weeks and see what grows out before pruning.
What might be expected from this year’s Norton grape harvest? I do not know. Similar situations have happened before. In Tennessee there was an Easter freeze in 2007. In Missouri, the Continental Climate Viticulture and Enology Institute hosted a workshop on the 2007 freeze and published the proceedings at http://extension.missouri.edu/explorepdf/winegrape/wg1001.pdf . The 2007 freeze was more severe than the 2012 event. Members from the institute surveyed the vineyard for damage by estimating the percent survival of primary, secondary and tertiary buds on the vines. When shoot re-growth commenced, the level of bud and vine injury due to the 2007 freeze was estimated.
A second survey was done before the 2007 harvest. Vines averaged 40 clusters per vine and weighed from 0.12 to 0.16 lb. per grape cluster. The Norton yield ranged from 0.6 to 1.0 tons per acre. Only 70% of primary buds on Norton vines were injured in the 2007 Easter freeze while other cultivars injury ranged from 95 to 100%.
What might be expected from this year’s Norton grape harvest? I do not know. Similar situations have happened before. In Tennessee there was an Easter freeze in 2007. In Missouri, the Continental Climate Viticulture and Enology Institute hosted a workshop on the 2007 freeze and published the proceedings at http://extension.missouri.edu/explorepdf/winegrape/wg1001.pdf . The 2007 freeze was more severe than the 2012 event. Members from the institute surveyed the vineyard for damage by estimating the percent survival of primary, secondary and tertiary buds on the vines. When shoot re-growth commenced, the level of bud and vine injury due to the 2007 freeze was estimated.
A second survey was done before the 2007 harvest. Vines averaged 40 clusters per vine and weighed from 0.12 to 0.16 lb. per grape cluster. The Norton yield ranged from 0.6 to 1.0 tons per acre. Only 70% of primary buds on Norton vines were injured in the 2007 Easter freeze while other cultivars injury ranged from 95 to 100%.
Based on the Missouri findings, I recommend we take advantage of this opportunity. Let’s start by counting regrowth on any five vines in each row over the next two weeks. For record keeping call the row closest to John Rice Blvd #1 and the row closest to Gresham lane # 5. The red arrow in the Google figure is pointing at the 1st row.
The vineyard soil test results are:
-------------------------------------Pounds per acre-----------------------------------------
pH P K Ca Mg Zn Cu Fe Mn B Na local in vineyard
6.6 10 210 2423 328 2.9 0 16 107 1 10 North half
6.6 10 186 2009 316 3.5 0.4 16 181 1 9 South half
UT Extension recommendation for the vineyard are:
In March evenly spread 1.5 lb. (4 cups) of 6-12-12 in a 10 ft. by 10 ft. area around each vine. When lime is needed use dolomitic limestone. If Mg deficiency appears apply ¼ cup of Epsom salts in a 10 ft. by 10 ft. area around the vine.
The vineyard is rated low in phosphorus (P). The vineyard soils are rated high in K and in sufficient in secondary and micro nutrients. Lime is not recommended at this time.
Other references
http://mtngrv.missouristate.edu/Publications/grapeguide.pdf
http://extension.missouri.edu/explorepdf/winegrape/wg1001.pdf
http://ohioline.osu.edu/b919/0010.html
http://www.ca.uky.edu/agc/pubs/id/id126/id126.htm
http://extension.missouri.edu/explorepdf/winegrape/wg1001.pdf
http://www.cals.cornell.edu/cals/grapesandwine/appellation-cornell/issue-5/grapes-101.cfm
-------------------------------------Pounds per acre-----------------------------------------
pH P K Ca Mg Zn Cu Fe Mn B Na local in vineyard
6.6 10 210 2423 328 2.9 0 16 107 1 10 North half
6.6 10 186 2009 316 3.5 0.4 16 181 1 9 South half
UT Extension recommendation for the vineyard are:
In March evenly spread 1.5 lb. (4 cups) of 6-12-12 in a 10 ft. by 10 ft. area around each vine. When lime is needed use dolomitic limestone. If Mg deficiency appears apply ¼ cup of Epsom salts in a 10 ft. by 10 ft. area around the vine.
The vineyard is rated low in phosphorus (P). The vineyard soils are rated high in K and in sufficient in secondary and micro nutrients. Lime is not recommended at this time.
Other references
http://mtngrv.missouristate.edu/Publications/grapeguide.pdf
http://extension.missouri.edu/explorepdf/winegrape/wg1001.pdf
http://ohioline.osu.edu/b919/0010.html
http://www.ca.uky.edu/agc/pubs/id/id126/id126.htm
http://extension.missouri.edu/explorepdf/winegrape/wg1001.pdf
http://www.cals.cornell.edu/cals/grapesandwine/appellation-cornell/issue-5/grapes-101.cfm
