Although almost never planted intentionally, elderberries occasionally appear in strange places, wherever their seeds get dropped by the birds or rodents who eat their berries. The blue elderberry, Sambucus mexicana / caerulea, is native and most common between California, British Columbia and the Rockies. The American elderberry, Sambucus canadensis, is more common elsewhere, and also appears in the west where it had historically been imported for berry production. Some modern cultivars (cultivated varieties) with gold, bronze, or lacy foliage are actually related to European elderberries.

Except for compact cultivars, elderberries grow rampantly to about fifteen feet tall and wide. Aggressive pruning in winter keeps them looking fuller and more densely foliated. Overgrown plants can be rejuvenated by getting cut to the ground. The big leaves are divided into seven leaflets that are two to six inches long. Blue elderberry foliage is softly serrate and a bit more variable, with five to nine leaflets that may be as short as one inch.

Wide flat trusses of pale white flowers that bloom in late spring or early summer produce small but potentially abundant and richly flavored berries. Blue elderberries are dark blue dusted with white powder on trusses to about six inches wide. American elderberries are darker and more purplish on trusses that can be wider than eight inches. (Red elderberries are toxic!)