Perennial native plants are foundations of a bioeconomy due to the lower input needs and more effective provision of ecosystem services compared to non-native annual plants (Tillman et al. 2006; Cox et al., 2006). In the Upper Midwest, where the landscape is currently dominated by corn and soybeans in the summer, and soils are largely bare in fall, winter, and spring, alternative crops that provides perenniality of the landscape is necessary. Many farmers in the Upper Midwest are interested in transitioning to more diversified perennial-based agricultural systems because of the ecosystem services these perennials can provide.
Elderberry (Sambucus canadensis), Black Elder, is a potential perennial crop that provides niche berry and flower ingredients used in Native American and pioneer cooking as well as for traditional medicinal purposes, while providing ecosystem services. Elderberry is a native fruit-bearing shrub common to Eastern and Midwestern North America. The plant is medium to large multiple-stemmed shrub. In the wild it occupies a wide range of habitats and exhibits considerable variability of form and growth habits.
Common habitats include well-drained, sunny sites, hedgerows, and is often found along streams and roadside ditches. Elderberry produces showy flat cymes of white flowers in June followed bright purple to black berries in late summer. Some bloom and fruit once, being determinate, while indeterminate elderberry continuously bloom and fruit yielding multiple crops of flowers and berries in a good year such as 2015.
Interest in cultivated elderberry production is being driven by consumer demand for health, nutrition, and wellness products. With European production currently dominating the market, US producers are attempting to jumpstart a domestic industry creating potential economic source for Minnesota farmers. In cultivated setting, elderberries generally begin producing harvestable yields 2-3 years after being planted as cuttings, and under ideal conditions, yields can approach to 8,000 pounds/acre in the southern Midwest. Commercial production of elderberry is becoming a vital part of sustainable agriculture in North America, and the number of acres dedicated to elderberry cultivation is growing. In Minnesota, this is evidenced by the establishment of the Minnesota Elderberry Cooperative in 2012. As such, cultivation of elderberry in Minnesota is recent phenomenon. However, the elderberry cultivars and planting materials currently used commercially in the state may not be the best suited to Minnesota’s growing conditions.
The development of an elderberry industry in Minnesota will depend on the resolution of several bottlenecks that must be addressed: First, there is a limited/lack of high quality planting materials that is adapted to Minnesota; second, because this is a new crop in Minnesota, one that is quite different from the dominant agronomic crops, there is limited knowledge about basic production practices both in monoculture and integrated systems; and 3) the lack of understanding of its market potential in Minnesota.
Developing the management recommendations that both enhance the environmental benefits conferred by elderberry and maximize their profitability will be essential to fulfilling our long term goal of developing a regional bio-economy based on native perennials that sustain both people and the ecosystem. Elderberry uniquely provides a multifunctional set of biological characteristics from a widely spreading, relatively shallow root system providing erosion control and wildlife habitat for birds, a wide range of prairie and oak savannah animals, dozens of native pollinators. Developing good management techniques present the potential to provide this environmental service as well as produce berries and flowers for human use as noted previously. In the field some elderberry cultivars convert large amounts of nitrogen to stem, leaf and fruit through its ability to grow rapidly and bear fruit in commercially viable quantities with annual cutting to the ground. The plant’s ability to regenerate itself annually could be effective in reducing nitrogen run-off, with the properly researched and tested horticultural management as applied to specific cultivars, both currently known and those yet to be identified.
Breeding and Genomics
There is limited selection of elderberry (Sambucus) cultivars that farmers can use in the production systems. Developing new cultivars for the Upper Midwest from existing, yet undocumented Minnesota elderberry germplasm is necessary. A genomic and breeding study will be employed around Minnesota to evaluate wild-sourced elderberry against the cultivars that are currently being used by Minnesota farmers to address bottlenecks of elderberry adoption and to accelerate its promotion in the landscape. Simple production efficiency of berries and flowers within general quality characteristics from even ripening, berry hold, weight, sweetness and acidity for traditional use in foods, brews and spirits will be evaluated through the breeding program. Others might more efficiently provide land management services and still yield a crop suitable for food ingredient design such as colorants and antioxidant rich freeze dried powders.
As indicated, long-lived woody perennials such as elderberry are likely to be foundation crops for diverse evergreen agricultural systems, with multiple ecological benefits. Because elderberry is a new crop in Minnesota, there is a dearth of basic research-based agronomic information on them, so as when they are planted in integrated systems such as agroforestry.
The elder’s widely spreading, moderately deep root systems hold soil in place and reduce leaching, thereby preventing soil erosion and protecting water quality. Elderberries are suited to both small and large scale production. It can fit into many small niches in the agricultural landscape. They can add economic value when planted in integrated systems such windbreaks, living snow fences, riparian buffers, alley cropping, contour strips, CRP and other marginal lands. Elderberries make it profitable for farmers to retire from annual agriculture those portions of agricultural landscapes that are least suited to it and which contribute the most to environmental degradation, such as steep slopes and areas prone to flooding. Their cold hardiness and later blooming cycle prevent them from the risks associated with an early frost: young shoot, emergent growth damage and flower loss, so that exposure to early spring sun is a benefit to their cultivation and not a risk, as it is for so many commercially grown fruits.
Recommendations from Oregon, New York and Missouri are not completely transferable because of the differences in environmental growing conditions in Minnesota; thus agronomic research to understand production using various agronomic practices is necessary. Although elderberries grow in a wide range of soil conditions, growth performance needs to be evaluated vis-à-vis site selection and preparation, establishment practices (planting design and weed management), and fertility management (nutrients needs). Coppicing and pruning systems for rejuvenation of mature plants is necessary to optimize elderberry production but is a major concern among elderberry growers because of the impacts these practices have on fruit production and quality. While elderberries are relatively pest resistant, several potential problems exists that impact commercial production. Pest management strategies should be identified to minimize impacts.
Elderberries have strong market potential. Elderberry plants are used for both their berries and flowers in juices, jams and extracts for their health properties; as flavor sources for foods and spirits; and as natural colors for foods and cosmetics. These markets are likely to grow as appreciation of the health value of the berries, for instance, increases.
More nutrient-dense than most other berries, elderberry juice, flowers, and extracts possess antiviral, immune modulation and anti-inflammatory properties. Elderberry-seasoned foods also exist in the market. Because of these market potential, there is a need to develop the market for Minnesota produced elderberry products.
An understanding of the effects of growing conditions, harvest, storage and processing on berries and flowers is also necessary. Changes in nutritional or functional properties and ways to mitigate issues need to be evaluated and understood so that farmers can maximize their profits and their market potential.
Other needs and challenges: Considering environmental challenges pose by agricultural intensification in Minnesota, there is a need to evaluate and explore the use of elderberry primarily for environmental protection and conservation using different planting designs. Elderberry can justifiably serve from a horticultural purpose as a windbreak or riparian buffer planting, without regard to direct economic production from berries and flowers, yet can produce salable product to reduce the cost of land management can open the door to technological and biological innovation in its harvest and use as an ingredient colorant or medical supplement.
For example, elderberry planted as part of a riparian buffer should be managed, harvested and processed differently from a primary crop agricultural installation aimed at producing berries for wine or juice. This will provide the opportunity to explore and increase use of mechanization and bulk techniques for ingredient production at lower costs per unit. In other words, a lower price per unit of flowers or berries is justified because the primary purpose for the plant is environmental, management principle/statute satisfying.
Kevin Dorn, Post Doctoral Research Associate, Kansas State University
Emily Hoover, Professor, Department of Horticultural Science
Tonya Schoenfuss, Associate Professor, Department of Food Science and Nutrition
Craig Sheaffer, Professor, Department of Agronomy and Plant Genetics
Don Wyse, Professor, Department of Agronomy and Plant Genetics
Diomy Zamora, Extension Professor, University of Minnesota Extension