Homegrown Habitat, October 2023: Highbush Blueberry
Blueberries are bird-friendly native plants with autumn flair. Homegrown Habitat is written by Sarah Middeleer, a landscape designer and vice president of Connecticut Audubon’s Board of Directors. Write to Sarah at homegrown@ctaudubon.org.
Who doesn’t love blueberries? Their delicious summer fruit is packed with vitamins and antioxidants; all sorts of health benefits are attributed to them. Their subtle spring flowers, small white and pink bells, are lovely to look at and entice pollinators. But blueberries become showstoppers in fall, with foliage that turns brilliant red, orange, and purple. In winter their beautifully textured bark ensures the blueberry’s status as a garden plant with four-season interest.
Highbush blueberry (Vaccinium corymbosum), native throughout Eastern North America, makes an excellent substitute for the non-native burning bush (Euonymus alatus), a thug sold by garden centers because customers love its scarlet fall color. Burning bush has invaded our woodlands and other natural areas, crowding out native plants that provide valuable food for wildlife. Highbush blueberry grows with a habit and texture similar to burning bush but offers marvelous wildlife habitat value.
A cousin, lowbush blueberry (Vaccinium angustifolium), is native to Canada and several central and mid-Atlantic states, according to BONAP (the Biota of North America). It is common in Maine, New Hampshire, and Vermont. Its fruit is smaller than that of highbush but is said to be sweeter. I have encountered lowbush blueberry on rocky outcrops in Maine, where it spreads in attractive colonies. Its foliage feeds over 300 species of moths and butterflies, its flowers provide pollen and nectar for bumblebees, and its fruit feeds many birds and mammals.
Highbush blueberry, said to be among the top shrubs for pollinators and songbirds, is indigenous to Connecticut. Its flowers attract several native specialist bees. Native bumble bees vibrate their wings, a technique known as buzz pollination, to extract pollen. Besides its fruit, which attracts many mammals and songbirds such as Gray Catbirds, Scarlet Tanagers, and thrushes, among others, highbush blueberry leaves are enjoyed by more than 200 moth and butterfly caterpillars. Caterpillars are prime nestling fare and are therefore critical to maintaining healthy songbird populations.
Growing six to 12 feet tall and similarly wide, highbush blueberry can be used in many ways: in a mixed native plant hedgerow, as a specimen, or as an understory plant in a woodland garden. Try a massing of blueberries, perhaps interspersing them with another cousin, black huckleberry (Gaylussacia baccata). Using more than one in close proximity will help to increase fruit yield.
Although blueberry is amenable to part shade, it will fruit most prolifically and display its best fall color in full sun. Given space, highbush blueberry will grow in an upright, rounded shape and may develop a vase shape over time. Years ago, at Broken Arrow Nursery in Hamden, I admired a highbush blueberry growing as a specimen on a slope near the barn. It was a stunning vase-shaped, petite, multistemmed tree, cementing my desire to grow blueberries of my own.
Highbush blueberry is highly adaptable to different conditions, with the caveats that it needs acidic soils (pH 4.5-5) and good drainage. In the wild it is often found in wet areas but also, confusingly, on rocky hillsides. Tom Andersen, director of communications for Connecticut Audubon, reports that he has loads of blueberry and huckleberry thriving on a ridge with poor, thin soil.
The Penn State extension website (link below) explains that blueberries are in the same family (Ericacea) as rhododendrons and mountain laurels, who all require porous, acidic, rich soils. When blueberries grow in wet areas, they will be found rooted into raised areas, often made of sphagnum moss or other organic matter. Thus, if you want to include blueberries in your rain garden, be sure to plant them along the higher edges of the basin so that their roots will never be inundated for long.
Regardless, a soil test in advance of planting is strongly suggested, in order to allow time for adjusting the soil chemistry if needed. Once planted, blueberries will benefit from an acidic mulch, such as a mix of pine needles and oak and maple leaves.
My own experience growing highbush blueberries is embarrassingly terrible. I’ve tried planting them in different locations, always with plenty of organic, rich soil. But the results have been dismal. Note to self: get a soil test. May you all have better results. And then please share your techniques with us!
Milan Bull, senior director of science and conservation at Connecticut Audubon, reports that many of our sanctuaries have blueberries — but that deer browsing has been a problem (although Tom Andersen, who lives near the Connecticut-New York border, says that deer always avoid the blueberries bushes in his neighborhood). Andy Rzeznikiewicz, land manager at Pomfret and Trail Wood Preserves, reports that highbush blueberries are present on the old golf course section of the Bafflin Sanctuary.
Here’s hoping that, wherever you roam this season, you will enjoy some blueberries in their autumn finery.
Resources
Anna Fialkoff and Heather McCargo, Native Groundcovers for Northeast Landscapes, 2022, Wild Seed Project
Anna Fialkoff, Native Shrubs for Northeast Landscapes, 2023, Wild Seed Project
Mark Richardson and Dan Jaffe, Native Plants for New England Gardens, 2018, Globe Pequot
https://extension.psu.edu/keys-to-establishing-a-successful-blueberry-planting
http://bonap.net/NAPA/Genus/Traditional/County
https://gobotany.nativeplanttrust.org/species/vaccinium/corymbosum/