Berberis aquifolium or Mahonia aquifolium
Berberis aquifolium or Mahonia aquifolium? That is the question, evidently, botanist cannot agree and keep shifting from one to the other. But it is the same plant no matter what they call it. It is also known as Mahonia piperiana, Holly-leaved Barberry, Broadleaf evergreen, Mountain Grape, Rocky Mountain Grape, Oregon Grape, or Oregon Grape Holly.
It is part of the Berberidaceae family of plants. Berberis aquifolium is native to North America. It is an evergreen bush. Aquifolium refers to the foliage meaning sharp-leafed. But this plant is neither related to Holly or grapes.
Berberis aquifolium has glossy green leaves, holly-like with spikes. The leaves change color in winter to shades of purple. Berberis aquifolium flowers in spring. The flowers are yellow and appear in large clusters. After flowering, it produces purplish-black berries. Berries attract birds, especially in winter. The berries are tart and contain seeds. They are sometimes consumed as jelly, wine.
Locate Berberis aquifolium in the sun or partial shade. Plant it in humus-rich, fertile, moist but well-drained soil. It adapts to most types of soils. And it is drought-resistant once established.
Berberis aquifolium is generally pest-free, but watch out for powdery mildew. The bark of Berberis aquifolium is sometimes used to make a yellow dye and the berries for purple dye.
Also read about Berberis darwinii or Berberis candidula