General Description

This large plant produces prominent clusters of flowers followed by blue-black berries.

Landscape

Often used to naturalize an area or as a hedge around ponds and streams. It’s also used to control erosion around wet areas. (University, n.d.)

Cultivation

This plant requires a sunny, moist location. It is tolerant of flooding. (Brun, 2021) Sambucus caerulea is prone to issues caused by nutrient deficiencies and having too many nutrients or minerals. It can also have trouble growing in areas that are too dry. (California, 2017)

Shape

The shape is a dense dome. The berries hang down in large clusters, pulling the branches towards the ground. They can be pruned to look like trees, but they are shrubs.

ID Characteristic

Blue to blueish-black berries, saucer-shaped clusters of white–yellow flowers, and the leaves which are pinnately compound. (Britannica, 2019)

Pests

This shrub is susceptible to soft scales, specifically European fruit lecanium, aphids, specifically the bean aphid, and elder borers too. It’s also prone to canker diseases including Botryosphaeria canker, Nectria canker, Diaporthe stem canker, and the dieback that results from them. (California, 2017) Along with this wood decay, leaf spots and stem spots can be an issue. (California, 2017)

Habitat

The Blue Elder is an understory species. It can be found in damp forests on slopes, streambanks/streamsides, and canyons. It can also be found in moist sections of a dry climate such as, along the sides of roads and within other mountain plants. (Stevens & Nesom, 2003)

Bark/Stem Description

The stems are soft, containing a sponge-like pith. Eventually, the stems grow to make a dense shrub or tree. The stems are poisonous so caution should be used when handling. (Brun, 2021) The bark is thin with wart-like lenticels and ridges. (Canada, 2015)

Flower/Leaf Bud Description

There is no terminal bud, however, there are lateral buds. The lateral buds have scales and are in groups of 2 or 3. They are typically between 1-2 cm long and are a green or brown colour. The leaf scars are triangular and large, usually with 5-7 vein scars. (Canada, 2015)

Leaf Description

The leaves are coarsely serrated, irregular at the base and are narrow ovate in shape. They are opposite, pinnately compound. Each leaflet is between 1-5 cm wide and 5-15 cm long. The leaflets are typically in groups of 5-7 (Breen, 2021). The leaves are poisonous since they produce cyanide. Special consideration should occur when handling fresh leaves. (Brun, 2021)

Flower Description

Yellow white in colour, 10-15 cm wide cymes. They are typically in bloom between May and July (Dirr, 2009). Pollination is commonly done by the wind. There is no nectar in the plants, so insects are not attracted to them. There’s also an argument over whether or not Sambucus caerulea is self-pollinating. In the wild they seem to be, however; in cultivation, they do not appear that way. (Fried, et al., 2016)

Fruit Description

The fruit are small and round, 3-5 mm in diameter, blue–black, with an occasional white coating. They ripen in the autumn and are sweet tasting. The fruit is found in clusters that droop down towards the ground. (Canada, 2015)

Colour Description

The fruit is a dark blue or blue-black colour, while the flowers are white. The buds are green or brown and the twigs are a lighter colour than the buds. Tops of the leaves are a blue–green colour and the bottoms are slightly lighter. (Canada, 2015)

Texture Description

This plant has thin stems which have a scale and wart-like texture on them. The leaf buds create a large triangular shape on the bark. (Canada, 2015)

Notable Specimens

University of British Columbia Botanical Garden in Vancouver, British Columbia, Canada has three wonderful specimens. (Garden, 2021)

Propagation

Sambucus caerulea can be propagated through seeds, cuttings, and transplantation. Propagation has the highest success when done through seeds. To do this the berries need to be gathered when they are ripe, dried and the seeds need to be separated from the berries. This is done through multiple methods, however, the easiest is to crush and dry the fruit while keeping the fruit and seeds together. When sown outside the seeds require two springs to germinate and must be about half a centimetre in the ground (Stevens & Nesom, 2003) If sown in a greenhouse the seeds spend about two months between 21°C and 30°C. They are then cooled to room temperature and planted after one season of growth occurs (Stevens & Nesom, 2003).Cuttings tend to be harder to propagate. Cuttings should contain at least two nodes and be at least 25 cm long from the previous seasons growth. When transplanting, the plants should be pruned to 50% of their height or about 1 m - whichever is largest. The plant should be transplanted by the root ball, which should be kept wet. The hole that the root ball goes into should be roughly 1 m deep. The soil should continue to be saturated with water, specifically through the first growing season (Stevens & Nesom, 2003).

Ethnobotanical Uses (Disclaimer)

The blue or purple berries of this plant can be and often are eaten. These berries can be made into wine, pies, jams, sauces, and syrups. They can also be eaten fresh and dry. The flowers can be made into tea and used for many things including treating headaches and indigestion. If the leaves or flowers are made into a wash they can be used for bruises and sprains, or to treat minor sores on domestic animals (Stevens & Nesom, 2003). Blue Elder twigs and fruit can be used to make natural dyes also. Traditionally the branches were used to make whistles, flutes, clapper sticks, and arrow shafts (Stevens & Nesom, 2003).

Fried, D., Hayden, J., Mase, G., Hardie, T., Mary Sisock, P., Tori Lee Jackson, M., . . . Peronto, M. L. (2016). Growing Elderberries: A PRODUCTION MANUAL AND ENTERPRISE VIABILITY GUIDE FOR VERMONT AND THE NORTHEAST. Vermont: UVM Center for Sustainable Agriculture, University of Vermont Extension. Stevens, M., & Nesom, G. (2003, June 03). BLUE ELDERBERRY Sambucus nigra L. ssp. caerulea (Raf.) R. Bolli. United States Department of Agriculture Natural Resources Conservation Service: Plant Guide, 1-5.