The carrot plant, Daucus carota subsp. sativus, is a familiar vegetable typically cultivated as an annual crop for its enlarged root, even though it is biologically a biennial plant. This herbaceous member develops its edible root and foliage in the first year before attempting to flower in the second. Understanding the visual characteristics of its underground and above-ground structures offers a detailed look into the life cycle of this common food source.
The Edible Taproot Structure
The edible taproot serves as the plant’s food storage organ. This root can vary significantly in shape, ranging from long and conical to cylindrical or globular, with the lower end typically blunt or pointed. Cultivated varieties are known for their orange color due to beta-carotene, but the roots are naturally found in diverse colors, including purple, white, and yellow.
A cross-section of the mature taproot reveals two main areas. The inner part, known as the core, is formed by the secondary xylem and surrounded by the vascular cambium. This core is encircled by the cortex, which is made up of the secondary phloem and forms the bulk of the root’s fleshy portion. The skin is generally smooth, and the interior texture is dense, though it can become fibrous if the plant matures past its ideal harvest time.
The Foliage and Growth Habit
Above the ground, the carrot plant forms a rosette of leaves that emerge from a compact central crown at the soil line. This rosette is the vegetative part of the plant during its primary growing season. The leaves are green and are often described as feathery or fern-like due to their highly divided structure.
The complex leaf structure is botanically termed tripinnate, meaning the leaves are divided three times into small, lacy segments. The leaf stems, or petioles, can sometimes have a slightly hairy texture. Before the plant bolts, the foliage typically reaches a height of only a few inches to about a foot, concentrating the plant’s energy into root development.
The Reproductive Stage
If the carrot plant is left unharvested and survives a cold period, it will enter its reproductive stage, a process known as bolting, typically in its second year. This transition shifts the plant’s energy from root storage to seed production. A tall, branched central flowering stalk emerges from the rosette, often reaching up to three feet in height.
At the top of this stalk, the plant develops a characteristic flat-topped flower cluster called a compound umbel. This inflorescence is composed of many tiny, densely packed white or sometimes pinkish flowers. Once the plant begins flowering, the stored starches in the taproot convert to sugars, causing the root to become woody, fibrous, and unpalatable. After the flowers are pollinated, they produce small, spiny seeds within segmented fruits called schizocarps.