Do Blueberries Need to Be Pollinated?

Pollination

• For blueberry pollination, a considerable amount of relatively heavy pollen must be moved by bees from the anther or male part of the blueberry flower to the stigma or female part. Bumblebees and other native bees are actually better pollinators for blueberries than honeybees -- because they are "buzz" pollinators, and their vibrations shake loose more pollen than a honeybee can move. One visit by a bumblebee will usually get the job done, compared with the need for three or more honeybee visits. When compatible pollen is deposited on a blueberry flower's receptive stigma it fertilizes the ovules, which produce the tiny seeds. These fertilized seeds stimulate larger berries to grow.

Cross-Pollination

• For fertilization to occur some blueberries require cross-pollination, or pollen either from another plant of the same variety or a different but compatible variety. Up to 90 percent of lowbush or native-type blueberries are self-sterile, meaning that they need another variety's pollen for fertilization. Cultivated northern highbush blueberry cultivars such as Bluecrop are self-fruitful, so pollen from another plant but the same cultivar is all that's required. Other highbush cultivars need cross-pollination, or pollen from another cultivar. Rabbiteye blueberries, grown throughout the South, are highly dependent on cross-pollination -- so much so that at least three different cultivars are usually planted.

Pollinators

• Native bees, often solitary or loosely social, are efficient blueberry pollinators -- and with minor effort you can encourage them to thrive. Less finicky than honeybees and willing to "work" under marginal conditions, native bees also aren't vulnerable to Colony Collapse Disorder and other maladies now afflicting honeybees. Providing them with food year-round -- wildflowers and a diversity of native plants, in addition to target crops -- is fairly simple. Shelter is even easier: buffer strips of bare soil or sand for ground-nesting bees and brush piles or wood scraps for wood-nesters.

Integrated Pollination

• For larger growers, it may be necessary to encourage native been populations and also rely on honeybees -- integrating the availability and needs of both. Introduce native bumblebee colonies to diversify your pollinators, because bumblebees will remain active when honeybees aren't. There are many other effective native bee species too. Don't bring in honeybees until blueberries are already blooming, because they may prefer other nectar sources if given the opportunity to find them. Both native and domestic bees are very vulnerable to pesticides, so avoid using potential toxins as much as possible.