Nigella sativa exhibits a stiff, branching stem, gray-green, threadlike leaves and gray-blue or white flowers. The flower forms a small fruit, or seed capsule, which releases seeds when it dries and cracks open. The seeds become black when exposed to the air and self-seed naturally in adequate climate and growing conditions. The plant grows to between 16 and 24 inches in height and blooms during the summer, giving off a strong aroma similar to strawberry plants.
Native to Mediterranean and Middle Eastern climates, Nigella sativa is now cultivated throughout northern Africa, the Middle East, and many parts of Europe. In the United States, it grows in U.S. Department of Agriculture Plant Hardiness Zones 2 through 10 and is tolerant of many growing conditions and soils. Nigella sativa requires full sun and decent drainage -- it will not grow well in boggy locations or consistently wet soil. These plants are drought-tolerant and, when cultivated, should be allowed to dry out between watering.
As a spice, Nigella sativa is used as dry, roasted whole seeds or ground into a powder to be mixed into curries and other dishes. Common names are black cumin and black caraway. These seeds are high in unsaturated fatty acids, fiber, and arginine and carotene, which are converted by the body into vitamin A. The seeds are pressed into an oil for medicinal purposes, which may be used in healthful cooking.
The black seeds of Nigella sativa have been used medicinally for centuries and are a central healing ingredient in Islamic tradition. The seeds and oil are valued for their anti-inflammatory properties and positive effect on respiratory problems, stomach and intestinal disorders as well as intestinal worms, kidney and liver function, improved circulation and immune system support. Modern medicine has shown Nigella sativa to contain anti-cancer properties and has been effective at suppressing tumor growth.