The taxonomy of the genus Sambucus L., originally described by Carl Linnaeus and hence its botanical authority, has been complicated by its wide geographical distribution and morphological diversity.

Elders are often grown as a hedgerow plant in Britain since they take very fast, can be bent into shape easily, and grow quite profusely, thus having gained the reputation of being 'an instant hedge'.

[11] Ornamental varieties of Sambucus are grown in gardens for their showy flowers, fruits and lacy foliage which support habitat for wildlife.

[14][8] Leaves, twigs, branches, seeds, roots, flowers, and berries of Sambucus plants produce cyanogenic glycosides, which have toxic properties.

[14] Ingesting a sufficient quantity of cyanogenic glycosides from berry juice, flower tea, or beverages made from fresh leaves, branches, and fruit has been shown to cause illness, including nausea, vomiting, abdominal cramps, diarrhea, and weakness.

[15][14][16] In August 1983, a group of 25 people in Monterey County, California, became ill after ingesting elderberry juice pressed from fresh, uncooked S. mexicana berries, leaves, and stems.

In a 100-gram (3+1⁄2 oz) amount, elderberries supply 305 kilojoules (73 kcal) of food energy and are a rich source of vitamin C, providing 43% of the Daily Value (DV).

Sambucus fruit is rich in anthocyanidins[22] that combine to give elderberry juice an intense blue-purple colour that turns reddish on dilution with water.

[23] Elderberry fruit or flowers are used as dietary supplements to prevent or provide relief from minor diseases, such as flu, colds, constipation, and other conditions, served as a tea, extract or in a capsule.

[24] Although practitioners of traditional medicine have used elderberries over centuries,[12] there is little high-quality clinical evidence that such practices provide benefits.

[22] In Japan, elderberry juice is listed as an approved "natural colour additive" under the Food and Sanitation Law.

[25] Fibres can be dyed with elderberry juice (using alum as a mordant) to give a "muted purple" shade.