Nigella sativa (black-caraway,[2] also known as nigella or kalonji), often called black cumin,[3][4] is an annual flowering plant in the family Ranunculaceae, native to south and southwest Asia. Nigella sativa grows to 20-30 cm (7.9-11.8 in) tall, with finely divided, linear (but not thread-like) leaves. The flowers are delicate, and usually colored pale blue and white, with five to ten petals. The black caraway fruit is a large and inflated capsule composed of three to seven united follicles, each containing numerous seeds which are used as spice, sometimes as a replacement for black cumin (Bunium bulbocastanum).