Wild About Blueberries

One of America’s oldest indigenous crops, wild (aka lowbush) blueberries are native to Maine and well-adapted to the harsh climate of the region. Curiously, blueberries require thin, acidic, glacial soil with low calcium content and have been comfortably thriving in Maine’s rocky, inhospitable barrens for over 10,000 years. This unique partnership has earned them the status of Maine’s beloved state berry. There are only about a dozen fruits which are native to North America and lowbush blueberries are among the handful of species that cannot be easily cultivated outside of their naturally occurring colonies, due to the highly specific growing conditions they require. Wild blueberries spread by seed, as well as through the growth of underground stems called rhizomes. Over a span of years, a seedling expands into a plant mat which can stretch anywhere from an inch to many feet in size as their rhizomes gradually grow outward. Since the mat spreads from a single origin, it is called a clone, meaning all the stems (and fruit) of that mat are more or less genetically identical. That said, the impressive genetic diversity existing throughout an entire field makes for delightfully complex flavor profiles in fruit harvests, ranging from tangy and tart to succulently sweet. 

In contrast to the wild lowbush blueberry (Vaccinium angustifolium) is the highbush blueberry (Vaccinium corymbosum). While they both share the Vaccinium genus, they are distinctly different species and each have very different qualities. The most notable difference is that, unlike their wild counterparts, highbush blueberries can be cultivated. Highbush blueberries are one of the more recently domesticated fruits in North America and the first variety intended for farming was developed in New Jersey in 1911. Today, the United State is a global leader in highbush blueberry production, with cultivation spanning 38 states in four primary geographical regions: the Pacific Northwest, South, Midwest and Northeast. In 2023, the United States produced 711.2 million pounds of highbush blueberries, or 322,595 metric tons. A few genetically narrow varieties of highbush blueberries have been propagated for large-scale cultivation, allowing growers to produce a blueberry of consistent size. The highbush is the blueberry that can be found year round in the fresh produce department of most grocery stores. These large, uniform berries have more watery pulp comparatively, which means less fiber and less intense flavor per serving, whereas the smaller lowbush blueberry has a higher skin to pulp ratio, less water and more antioxidant rich pigment, fiber and flavor. Highbush blueberries are often picked before fully ripe and stored for up to 2 months being shipped thousands of miles after harvest, as well. I have room in my heart (and stomach) for any and all blueberries, but for clarity’s sake, we will stay focused on the pièce de résistance that is the wild lowbush blueberry for the rest of this article. 

The people who work with wild blueberries are referred to as stewards, and they use best practices handed down through generations of caretaking to tend to the barrens. Maine is the leading producer of wild blueberries in the United States, with approximately 47,600 acres of blueberry barrens being managed on 512 farms statewide. The Passamaquoddy and Wabanki people were some of the first to harvest wild blueberries thousands of years ago and these fruits are of great cultural significance to the Tribes. Among the many conventional and organic farms managing barrens in Maine presently, The Passamaquoddy Wild Blueberry Company (PWBC) in Columbia Falls is the largest Native American-owned wild blueberry farm in the world. Tribal members have been managing this natural resource and harvesting wild blueberries by hand on their 2000 acres of barrens for the past 40 years. The Passamaquoddy Wild Blueberry Company provides full-time, year-round, and seasonal jobs for Tribe members and by purchasing wild blueberries from PWBC, you are supporting the Tribe’s prosperity and economic development initiatives (as 100% of profits are reinvested in future growth or distributed to the Tribe). Founded in 1874, Wyman’s of Maine is the largest conventional lowbush blueberry producer in Maine. They own and manage over 17,000 acres of barrens from Down East Maine to Eastern Canada and process up to 2.3 million pounds of wild blueberries daily during summer harvest from the acres they own in Maine alone. Wyman’s employs about 200 people year-round and more than 500 during peak harvest season and grows for companies such as Costco, General Mills and Walmart.  

Every season is important in the life cycle of the wild blueberry. In the springtime, the blueberry plants stir from their winter dormancy, cloaking rocky barrens in a thick carpet of glossy, reddish- and lime-green foliage. Buds swell and bring forth dense clusters of pale white and pink-tinged blooms (up to 16 to a bud!). It is at this time that bees begin to play their invaluable role in fruit production as pollinators. As “keystone organisms” in our ecosystems, bees are essential for maintaining the integrity, productivity and sustainability of many types of ecosystems, including agricultural crops, fruit crops, and backyard vegetable and flower gardens. More than 50 species of native bees have been observed pollinating Maine blueberry fields and they are historically responsible for most of the wild blueberry pollination that takes place. In large part due to habitat loss, as well as the application of toxic pesticides and fungicides to fields, there has been an alarming decline in native bee populations over the past several decades. Farmers have had to increasingly rely on managed beehives for pollination of lowbush blueberries. According to the University of Maine Cooperative Extension, “Honey bees are the ‘workhorses’ of managed bees and some estimates suggest that honey bees account for 80% of the insect pollination in agricultural crops. The use of the honey bee in lowbush blueberries has increased tremendously over the past 40 years. In 1965, almost 500 honey bee colonies were brought into Maine for lowbush blueberry pollination. By 1985 about 25,000 honey bee colonies were brought into Maine for lowbush blueberry pollination, but by the year 2000, more than 60,000 colonies were brought into Maine for pollination of this crop.” Unfortunately, there are several drawbacks associated with using honey bees for blueberry pollination. Some significant drawbacks are possible aggression and defensiveness of their hives, the fact that they originate from warmer climates and usually will not fly when Maine’s chilly Springtime temperatures drop below 50℉, and (because they are generalists), they will sometimes switch from foraging on the intended crop to more rewarding wildflower species they discover. Additionally, blueberries are notoriously difficult for honey bees to forage on, as the opening of the small, bell-shaped flowers are usually too narrow for the bees to access the pollen-containing anthers. This means that pollination rates tend to be quite low compared to those of more specialized native bee species, even when adequate numbers of honeybees are supplied with a sea of flowers to forage on. Because honeybees directly compete with native bees for resources, the number of native bees and their effectiveness in pollinating blueberry crops that are stocked with managed hives is also further diminished. 

During the summer, blueberry foliage darkens somewhat and fields burst into rich shades of purple and blue as their fruit set begins to ripen. These stunning shades of blue are owed to pigments called anthocyanins and berry color can range from light, powder blue to jet black. Anthocyanins are responsible for the charming “blueberry stain” and are a type of nutrient called a flavonoid. Flavonoids have been studied extensively in the past 25 years and research indicates that eating foods high in flavonoids regularly may support cognitive and metabolic health. Blueberries are picked at peak ripeness from July to early September (season length can vary depending on the region and the weather conditions in any given year) and sold at markets or frozen within days of harvesting. Due in part to the rocky, uneven terrain of blueberry barrens, harvesting is still largely carried out by hand using a specialized close-tined rake, but mechanized harvesters are gaining popularity. The berries are generally sorted, cleaned, and processed within hours of being picked. 99% of the wild blueberry crop is flash frozen within 24hrs of harvest to lock in maximum flavor and health benefits. Humans are not the only animals that revel in the annual blueberry harvest: Black bears, moose, foxes, raccoons, skunks, opossums, deer, porcupines, mice, chipmunks and birds (such as turkeys, grouse, chickadees, catbirds and thrushes) are all among the wildlife that consume wild blueberries.

The fall is arguably the most visually stunning season in the blueberry’s lifecycle. As the plants begin to die back and return to a state of dormancy, their foliage transforms from a rich green color to vivid shades of burgundy, maroon and purple. Vast landscapes are seemingly set ablaze by the intensely saturated color. I find few contrasts so striking as a lowbush barren adorned in flaming red foliage complementing an arctic blue sky in late autumn. Sometime after the first killing frost, fields are mowed for the winter and, depending on weather conditions, farmer’s may also burn at this time. Blueberries are managed on a two-year crop management cycle, meaning only half of a farm’s fields are cultivated in any given year, while the other half is left to rest. The practice of burning fields extends back to the earliest Native Americans who were managing the barrens. The burn kills insects and helps to control fungus and other pests that may be lying dormant in the fields, and also destroys many weeds, weed seeds on the soil surface, and small trees that may be competing with the crop. The practice has been proven to significantly stimulate fruit yields when done biennially, as well.  Burning may be applied anytime the weather conditions allow (it must be dry with no wind) between the Fall and April, after the first killing frost and before plants resume their growth in the Spring.