The carnation (Dianthus caryophyllus) is a globally recognized flowering plant prized for its ornamental value. Originating in the Mediterranean region, this herbaceous perennial has been cultivated for over 2,000 years, resulting in a vast array of cultivars. This description explores the physical characteristics of the carnation, including its complex bloom, distinct foliage, and broad color range. Its structure, texture, and coloration contribute to its lasting popularity in gardens and floral arrangements.
The Distinctive Flower Head
The most recognizable feature of the carnation is its voluminous, often rounded flower head. This bloom is characterized by numerous, densely packed petals, which give the flower a lush, globular shape. The edges of these petals are typically frilled, ruffled, or toothed, creating a soft, intricate texture that distinguishes the carnation from other flowers.
Standard carnations commonly measure between one and three inches (3 to 7 cm) in diameter, although larger, giant-flowered varieties can reach up to four or five inches across. The petals of modern cultivars are generally described as “double,” meaning they have many more than the five petals found on the wild species, which contributes to their full appearance. These flowers are borne either singly at the tip of the stem or in loose clusters of up to five blooms.
Supporting the base of the petals is the calyx, a firm, cylindrical structure. This green, cup-like sheath is formed by five fused sepals, which persist after the petals have faded. At the base of the calyx, two or three pairs of small, overlapping bracts form an epicalyx, a collar-like structure. This firm base helps stabilize the flower head and allows the heavy, double blooms to remain upright on the stem.
Stem and Foliage
The plant is supported by rigid, upright stems that can reach heights of up to three feet (one meter) in varieties grown for the florist industry. These stems are straight and stiff, making carnations ideal cut flowers. They are characterized by noticeable swellings, or nodes, at regular intervals, which mark the points where the leaves emerge.
Carnation foliage provides a striking contrast to the vibrant flowers due to its distinct coloration. The leaves are typically a glaucous, grayish-green or blue-green hue, resulting from a thin waxy coating on their surface. They are long, narrow, and strap-like, often reaching up to six inches (15 cm) in length.
These leaves grow directly opposite each other on the stem. The base of the leaf sheaths, or wraps around, the stem at the nodes. This arrangement of blue-green, waxy leaves on a jointed stem is a defining characteristic of the Dianthus genus.
Common Color Variations
The carnation is available in a wide spectrum of colors, making it one of the most versatile commercial flowers. Naturally occurring colors include shades of pink, white, red, and yellow, with the original wild species exhibiting a pinkish-purple color. Cultivation has expanded this palette to include deep burgundies, oranges, peaches, and greens.
Beyond solid colors, many cultivars display variegated patterns, featuring stripes, flecks, or picotee edges of a contrasting color (e.g., red-and-white or pink-and-white combinations). Pure white carnations are often used for artificial coloration, as their petals readily absorb pigmented water. This allows for the creation of bright, unnatural shades, such as true blue, which is not found in any natural cultivar.