DRIP IRRIGATION FOR GRAPES ArstHortSoc 101st:114-19 1980

When fruit set and rainfall are sufficient, grape yields in Arkansas are high, but rain is not always sufficient in Arkansas. There is enough, in terms of inches, but it often comes at the wrong times. Records during the past 20 years have shown that in all but 3 years in Northwest Arkansas, there have been brief dry spells during the growing season that lasted for at least two or three weeks. These dry periods stress the vine and affect fruit growth, and extended dry spells play havoc with a grape crop. Fruit growers have considered grapes to be the least responsive of the fruit crops to supplemental irrigation due to their extensive root systems. However, research at the University of Arkansas has shown that what really happened over the years was that grape growers have been adjusting the fruit load (number of fruiting nodes left per vine) to a level that would allow for the crop to mature even when the annual drought occurs. Another reason that the 'Concord' producers of Northwest Arkansas have not considered using irrigation was the lack of irrigation water sources. The concept of drip irrigation conserves water and has helped to alleviate this problem.