According to scientists from Agricultural Research Service (ARS), important pollinators are quite essential to get a great rabbiteye blueberry harvest, especially native southeastern blueberry bees, although growers can bring in managed honey bees to do the job.
For commercial rabbiteye blueberry producers in Mississippi and Louisiana, this analysis is particularly true. When growers have sufficient pollinators, they would be able to increase the percentage of flowers setting fruit from 10 - 30 percent to 70 percent or more. A mature rabbiteye blueberry bush can produce as much as 15 pounds of berries.
Also, berries that are fully pollinated are mature and bigger earlier than fruit from inadequately pollinated flowers. As a result, bee-pollinated flowers produce fruit that brings a premium in the marketplace.
Research entomologist and co-leader of the study, Robert Danka from the ARS Bee Breeding, Genetics, and Physiology Research Laboratory in Baton Rouge, Louisiana, said that they looked at multiple species of bees to see which did the best job of pollinating rabbiteye blueberries. They tested honey bees, native bumblebee species, southeastern blueberry bees, and carpenter bees.
According to Danka, among all of these bees, only the southeastern blueberry bee and the honey bee significantly increased fruit set. He explained that the native southeastern blueberry bee did the best job.
However, the only means for commercial growers to have enough southeastern blueberry bees to provide a superior level of pollination is to provide habitat on the edges of their fields that encourage their population to grow.
Research entomologist Blair Sampson with the ARS Thad Cochran Southern Horticultural Laboratory in Poplarville, Mississippi, explained that what commercial growers can do is to provide woodlands near the edge of their fields since that's where southeastern blueberry bees prefer to nest. They are ground-dwelling bees that like shades and lead litter but don't like wet or soil heavy with organic material.
According to Sampson, there is a potential for a small grower with 1 - 3 acres of blueberries to get by solely with the pollination of native bees, particularly if they have encouraged them with attractive habitat. But a grower with fields of 25 acres and more should probably consider supplementing by bringing in honey bees colonies.
In the study, from year to year, depending on rain and other weather conditions, the population of some southeastern blueberry bee vary greatly, and this is complicating the matter while other populations were reliably present every year.
Explaining further, Sampson noted that a farmer who sees that during the first few days of bloom they are not getting prolific visits from the native bees should probably arrange to bring in some honey bee colonies. But even that may not guarantee ample pollination because there is no way to be sure honey bees will stay on blueberries if there is something else in bloom that is more attractive to them.
