Blueberries are native to North America and are comprised of many different species under the genus Vaccinium. Northern highbush (V. corymbosum) are taller than lowbush (V. angustifolium) and more cold tolerant than southern highbush and rabbiteye (V. virgatum syn. V. ashei) blueberries. Blueberries can be used as both fruit-producing and ornamental plants for Pacific Northwest gardens. They bear abundant crops from late June through September, depending upon the cultivars grown and the region in the state they are planted.
A one cup serving (148 grams) has only 84 calories, 1.1 grams of protein, and can supply 14.4 milligrams of vitamin C (National Nutrient Database 2011), presenting 24% of the suggested Daily Value for vitamin C. The recommended daily intake by the U.S. Food and Nutrition Board of the Institute of Medicine for men more than 18 years old is 90 milligrams of vitamin C daily; for women more than 18 years old, it is 75 milligrams daily (National Institutes of Health 2015). Blueberries are also relatively rich in potassium, supplying approximately 3% of a person’s daily value per one cup (148 g) serving.
The Blueberry Plant
Blueberries are shallow rooted, deciduous perennial plants that can live for more than 40 years. There are four main types of cultivated blueberries and multiple cultivars from which to select.
The majority of Washington State gardeners choose northern highbush cultivars (V. corymbosum). These plants will grow from 5’ to 8’ in height and 5’ in width, if given full sun. The northern highbush cultivars are the preferred types for gardeners in the temperate zones of the United States, where mid-winter temperatures don’t drop below -20°F (Zone 5a, USDA 2012). They offer the highest and most consistent yields of all the different types of blueberries, and their fruit is commonly found in grocery stores. Cultivars are described in Table 1.
The second type of popular blueberries are called southern highbush (V. darrowi x V. virgatum). Cultivars released in this category were designed for the milder regions of the country, where mid-winter temperatures don’t drop below 0°F (Zone 7a). Southern highbush cultivars may be grown in Washington, but will have lower yields than northern highbush types (Strik et al. 2014). In addition they tend to bloom early in the season, when there are mild winters, making their flowers more susceptible to spring frost injury.