UD Extension researchers look to blueberries as a small wonder for Delaware
Blueberries,Vaccinium corymbosum, the tiny, sweet blue fruits touted for their health benefits are growing as a favorite among fruit lovers and health-conscious people everywhere. With consumer demand trending toward buying local, blueberries could be a no-brainer bonanza for the First State. For Delaware to do it right, knowing the best varieties to plant and documenting the ideal growing conditions for commercial production is essential.
At the University of Delaware College of Agriculture and Natural Resources and beyond, Emmalea Ernest is informally known as “the lima bean lady” in part for her research efforts to build a better lima bean, a vegetable crop that has enjoyed success and prominence in Delaware.
An Extension agent and fruit and vegetable researcher, based at UD’s Elbert N. and Ann V. Carvel Research and Education Center,Ernest works closely with her colleague, Gordon Johnson, Vegetable and Fruit Extension Specialist. Ernest’s efforts have focused on evaluating varieties of crops that can be grown in Delaware for commercial production. Though lima bean breeding remains her specialty and area of doctoral study, Ernest also conducts trials of sweet corn, lettuce, watermelon, pole beans and for the third year in a row, blueberries are part of her research repertoire.
“Not a lot of Delaware acreage is devoted to blueberries at present,” Ernest explains, “but there is a lot of interest from growers.” Ernest’s research will provide valuable information on what varieties produce the best yield and taste for success in Delaware.
Since 2011, rows of blueberries-in waiting occupy approximately a third of an acre at the Thurman G. Adams Agricultural Research Farm part of Carvel’s 344 acre complex. In all, each of 23 blueberry varieties, with names like Aurora, Sweetheart, Star, Reka, and Chandler, to name only a few, are part of the large, multi-year study. In addition to the Carvel site, Ernest is conducting variety trials and other studies in collaboration with Hail Bennett, of Bennett Orchards in Frankford.
In the first two years, Ernest and her “veggie team” have been pinching off the flower blossoms, preventing fruit production.
Stopping blossoms from progressing into blueberries allows the plant to become fully and firmly established. This summer, the third year of research has been the charm, or at least a change for the senses. Now, they will see and taste the fruit of their labors.
Ernest refers to her crop as “my blueberries” but she is willing to share their various shapes, sizes and flavors, as well as give credit to her team of interns and UD colleagues for the hard work. This summer, the study will benefit from volunteer Master Gardeners who will help harvest the 275-plus bushes as they ripen. Size, weight, color, taste and overall health will be logged in and evaluated. While she is curious to receive feedback from others about their taste and texture, Ernest’s trials currently concentrate on the results of soil amendments, mulching techniques and specific variety’s response to Delaware’s seasons and weather conditions. The varieties reach their peak at different times in the summer, important knowledge that will help growers to expand their production over several months.
Blueberries are relatively disease free Ernest explains, and while her research plot has yet to be picked off by birds, she anticipates they will be a major issue for the crop. Currently, uncovered, Ernest says there are plans to enclose the entire trial area with a trellis covered by one large net.
Also working closely with Ernest is Extension IPM Specialist Joanne Whalen, who monitors the plots for the presence of spotted-wing drosophila, a potential, pesky fruit fly for the crop. The best bird netting won’t stop visits from fruit flies, however. If the presence of the spotted-wing becomes more of an issue, Extension experts will seek to find a solution to the pest.
As the berries turn from green to blue and violet, they are picked and weighed from each bush. Taste tests at this stage are informal, with Carvel’s staff serving as willing taste critics.
Three different experiments are being conducted at the trial site. In addition to the variety trial, the team is evaluating blueberries’ response to various soil and mulches that she and her team apply.
Blueberries are traditionally planted with peat moss under the root, Ernest explains. They are evaluating less-costly alternatives. Materials being tested include pine bark fines, waste silage, composted saw dust horse bedding, chipped-up construction waste wood, and for control, no amendments at all. Mulching materials include the same list of ingredients, and also chopped corn stalks. The ongoing results are published in a vegetable and small fruit blog she and Gordon Johnson maintain, and articles also appear in the Weekly Crop Update.
“Blueberries like wet conditions,” Ernest says, acknowledging that a very wet June has been good for the blueberry’s first year of production.’They’ve been very happy this summer,” Ernest adds. “They do well in bog-like conditions, but they aren’t an aquatic plant,” she cautions.
Ernest plans to collect data for several more years before being comfortable making recommendations to area growers. Conducting successful variety trials, soil amendment studies and mulching recommendations can only be executed across an array of conditions and time. It is exacting work where patience is a virtue.
Ernest, ever the scientist, is nonetheless excited about the prospects of bigger and better blueberry crops in Delaware. “I think people will get more excited about them than lima beans,” Ernest admits. “I have no shortage of people offering to eat them.”
Article and photos by Michele Walfred