ORGANIC BLUEBERRY PRODUCTION AND OBSERVATIONS IN GEORGIA

Abstract

Georgia has an excellent window for organic blueberry production since much of the crop ripens ahead of production in the northern U.S. Major challenges facing Georgia organic blueberry growers are weed control, organic fertilization, insect control and disease control. A team of Georgia growers, extension agents and scientists are working together to solve these production problems. Since 2002 a series of experiments have been conducted on blueberry establishment and maintenance. Various mulch materials were tested. On young plants, pine straw produced the highest yields, but pine bark and landscape fabric were also successful. With the pine straw treatment, a respectable yield of 0.97 kg/plant occurred 24 months after planting. In addition, a bed shaper–plastic mulch layer was modified by developing a removable center. Using this system, beds are formed, plants are mechanically transplanted, plants are pruned to 75 mm, and plastic is then pulled over the stem. This produces a fairly tight fit around the stem and a nearly weed free system except for weeds growing from the edges. On mature plants, pine bark and wheat straw were tested. Wheat straw produced excellent weed control and improved blueberry growth in year one and two. However, pine bark mulch provided the best weed control in year three. Various organic burn down compounds such as vinegar, Xpress, Alldown, and Matran 2 were tested for winter weed control efficacy. In these trials Matran 2 was the most effective, and the product also performed well on woody weeds that were winter pruned, allowed to resprout and then treated. A propane torch was also tested, but discarded because of the fire hazard. Entrust insecticide was tested for thrips control and gibberellic acid for fruit set. Thrips populations were low, so no effect on fruit set was noted from Entrust. Gibberellic acid significantly improved fruit set.