Twinberry (Lonicera involucrata) is a member of the Honeysuckle (Caprifoliaceae) family that is native to northern and western North America, from southern Alaska to Quebec, and south through the western United States to California and to Chihuahua in northwestern Mexico.
It is a large shrub with elliptical leaves. Its flowers are tubular, hairy, 1-2 centimeter long. They are produced in pairs; each pair has a pair of reddish basal leaves. The fruit is a black berry 1/4 to 1/2 inch in diameter; each contains several small seeds.The fruit is edible but bitter and best left to the birds.
In California the two recognized varieties have differing ranges. Var. involucrata has mostly yellow flowers and is found in the Sierra. Var. ledebourii has mostly red-orange flowers and is found along the coast and in the Coast Ranges from Santa Barbara County northwards. It grows at elevations from sea level to 9500 ft.
In the garden, this plant likes regular water but can survive on reduced watering. The flowers are welcome in summer when many other plants have finished blooming.