vaccinium

Highbush blueberry (Vaccinium corymbosum) is one of the most beautiful, delicious, and creature friendly native shrubs in our
New England woods and swamps. As fall ripens, some trees and shrubs seem to turn color overnight and quickly drop their
leaves. Not so the highbush and others in its clan. Blueberries seem to accept the approach of winter only reluctantly, their leaves
slowly transforming from green to maroon and finally steamed lobster red. When we cleared a spot in our woods for the house, I
left as many of the highbush blueberries as possible, and now we have quite a mass of them mixed in with the laurels (Kalmia
latifolia) along the edge of the woods. I notice the first blush of red in their foliage around the end of September and marvel as
the last maroon and scarlet leaves fall from the youngest twig tips around thanksgiving. The gnarled, lichen-encrusted limbs of
older specimens are wonderful in the winter. Like many others in the Ericaceae, Vaccinium corymbosum continually sends up
new shoots from the base of older trunks to renew the canopy. The older trunks can live for fifty years or more and reach a
diameter of three inches near the base, but more typically they succumb to falling debris, borers, or old age when half that size.
Fortunately, if you give the plants a modicum of sunlight and care, the old limbs live on for decades, becoming more twisted and
lovely as time goes by. Truly old ones have the same gothic quality as a Spanish moss-draped live oak in miniature.

Highbush blueberry comes in to flower here
in late May, just as the queen bumblebees,
along with small solitary bees and flies are
becoming desperate for nectar. In ten
minutes last May I photographed six species
of bees, flies and a wasp feeding in the
flowers and apparently pollinating them. The
opening of the bloom is rolled back to
provide a lip for the insects to hang onto as
they enter and exit the flower. Bumblebees
are too large to fit inside the bloom and
either stick their tongue in the opening or
pierce the base of the flower, robbing the
nectar but largely circumventing the pollen
and thus effective pollination. Small solitary
bees enter all or partway into the flower and
I imagine they are more reliable pollinators.

Wild highbush blueberry fruits are typically small (6-10 mm) but strongly flavored. They tend to ripen erratically, so there are
always a few ripe ones in a branch but you have to forage over several bushes to pick enough fruits to make a meal. Without
question, older (more than 10 years) shrubs growing in full sun bear the most fruit. A highbush in shade may flower and
thus spread its pollen, but rarely fruits very much. Birds are very effective at monitoring the shrubs as well, so it is hard to
get a good crop without some attention and bird netting. Many highbush cultivars have been developed for commercial fruit
production, and all the large fresh blueberries found in supermarkets are harvested from these cultivars or hybrids between
V. corymbosum and closely related species. Many of these cultivars and hybrids have been selected for large size as well as
concurrent ripening, so you can get large crops of fruit off fewer plants than if you relied on wild ones. To spread the harvest
out over the season, select early, mid and late-ripening varieties recommended for you area. Fall Creek Nursery, a wholesale
source of plants, has some excellent information on many varieties and your local agricultural experiment station or extension
service may have recommendations for your area as well. A newly purchased blueberry bush will likely consist of a few main
trunks 2-3 feet tall. These will begin to flower within a year or so and bear fruit, but this will weaken the plant as it is trying
to get established. I prefer to prune recently transplanted specimens back by 1/3 in late winter to encourage a flush of new
vegetative growth from the trunks and more importantly, the base of the plant. These lower sprouts will shoot up over the
course of several years to eventually become larger, fruit producing branches once the plant is settled in. Acidic soils (pH
below 6) are important for good blueberry culture. Ideally, the shrubs should be mulched with either 2-3 inches of rotted
wood chips or compost each spring along with a sprinkling of a granular organic fertilizer (blueberries, like many plants in
the heath family, are sensitive to over fertilization with chemical fertilizer).