Nigella sativa aka Roman Coriander

Nigella sativa belongs to the buttercup family, Ranunculaceae. It is an annual: its life cycle takes one year. Gardeners know it as black cumin or common fennel flower. Its native range starts in Romania. It extends to western and southwestern Iran. It grows on farms, by roads, and on disturbed ground. People also grow it for its seeds, flowers, and oils. It suits both temperate and subtropical regions.

The plant grows upright and has many branches. It has a strong taproot, its main root. Its bright green leaves split into very fine parts. RHS gives a height of about 1 foot [0.3 metres]. Its garden size range reaches 1.6 feet [0.5 metres] tall and wide. Useful Tropical Plants gives a taller limit: 2.3 feet [0.7 metres]. It makes a small, bushy plant for garden beds.

The summer flowers are white with a blue tint. Each can reach about 0.11 feet [0.035 metres] across. Swollen pods form after the flowers and hold many seeds. Bees pollinate the flowers by moving pollen. The plant can also use its own pollen. Useful Tropical Plants says blooms appear around 100 days after sowing. Seeds may ripen about 50 days after blooms start. Ripe seeds have a strong scent. Some compare the smell to nutmeg.

Give this plant full sun and soil that drains well. RHS lists sand, loam, clay, and chalk as suitable soils. The soil can be acid, neutral, or alkaline. Keep it moist, but do not let it stay waterlogged. Choose a warm site with shelter. Sow seeds where they will grow, in mid-spring or autumn. The plant needs no pruning. RHS gives it a UK hardiness rating of H4. RHS also reports few usual pest or disease problems. Useful Tropical Plants warns it may slow nearby plants' growth. These include legumes, the pea and bean family.

Use it in flower borders, cottage gardens, or wildflower meadows. The flowers suit cutting, and the plant needs little care. The seeds add flavour to bread, cakes, curries, and pickles. People eat them raw or cooked and extract their oil. Unripe seeds taste bitter. As seeds ripen, they gain their prized scent. PFAF records past uses for gut problems and other health complaints. These records do not prove that such treatments work. PFAF also describes using the scented seeds to deter clothes moths. PFAF and Useful Tropical Plants report no known hazards. This does not prove safety for every use or dose.