The aromatic ingredient known globally as coriander originates entirely from a single plant species, the annual herb Coriandrum sativum. This plant is one of the world’s oldest cultivated herbs and spices, with evidence of its use dating back to ancient Egyptian times. It is a member of the carrot or parsley family, Apiaceae, which includes other familiar plants like dill and fennel. The widespread use of this plant has led to different parts of it being known by distinct names across various cultures and regions.
The Source Plant: Identification and Terminology
Originating in the Near East and Mediterranean regions, Coriandrum sativum is now grown worldwide for both its fresh foliage and its dried fruit. The species name sativum is a Latin term signifying that the plant is cultivated.
The most common source of confusion for consumers is the interchangeable use of the terms “coriander” and “cilantro.” In North America, the fresh, bright green leaves and tender stems are almost exclusively referred to as cilantro. This name is derived from the Spanish word for the plant, which itself traces back to the botanical name.
In contrast, the term “coriander” in American English typically refers only to the small, dried, bead-like fruits, which are used as a spice. However, in many other parts of the world, particularly the United Kingdom, the entire plant, including the leaves and seeds, is simply called coriander. The plant is also known by other names, such as Chinese parsley or dhania, depending on the country or cuisine in question.
Plant Morphology and Cultivation
Coriandrum sativum is a slender, annual herb that typically grows to a height of 1 to 2.5 feet (30 to 75 centimeters). It possesses a well-developed taproot, which is why it does not transplant well once established. The plant’s leaves change dramatically as it matures, a characteristic unique among plants in its family.
The basal leaves found near the soil are broad, fan-shaped, and resemble flat-leaf parsley. As the plant matures and begins to “bolt,” or send up a flower stalk, the upper leaves become finely divided, lacy, and fern-like. The flowers appear in flat-topped clusters called umbels, which are characteristic of the Apiaceae family, and are small, usually white or pale pink.
The plant is considered a cool-season crop that thrives in well-drained soil and full sun, but it can tolerate light shade. It is often grown from seed in early spring, and the foliage is typically ready for harvest in 45 to 80 days. If the plant is allowed to continue its growth cycle, it will produce the seeds, which are harvested when they are fully dried, about 100 days after planting.
Distinct Culinary Applications of Leaves and Seeds
The fresh leaves, or cilantro, have a bright, pungent, and distinctly citrusy taste. Because the flavor diminishes when exposed to heat, the leaves are best used raw, added as a garnish just before serving, or incorporated into fresh items like salsas and guacamole.
For some individuals, however, the fresh leaves have a strongly disagreeable soapy or pungent taste due to a variation in the olfactory receptor gene OR6A2. Despite this genetic divide, cilantro is a foundation of many cuisines, including Mexican, Thai, and Indian cooking, where it is used in chutneys and as a garnish. The roots of the plant also have a deep, more intense flavor than the leaves and are a traditional ingredient in some Southeast Asian pastes and curries.
The dried fruits, or coriander seeds, have a completely different, warm, nutty, and sweet-spicy flavor profile. When crushed, the seeds release a lemony citrus note primarily from the volatile compound linalool. They are often toasted or heated gently before being ground to enhance their aromatic qualities. Ground coriander is a foundational spice in many blends, including Indian curry powders and garam masala, and is used to flavor meats, baked goods, and pickling brines.