The carnation, Dianthus caryophyllus, is a long-cultivated ornamental flower prized for its ruffled petals and long vase life. Known for their versatility, carnations are available in a wide spectrum of shades. This color diversity results from both the flower’s natural genetic makeup and the ingenuity of breeders and scientists, contributing to its enduring appeal in the global flower trade.
The Natural Color Palette
The colors found in wild and traditionally bred carnations are determined by two main types of plant pigments: anthocyanins and carotenoids. Anthocyanins are responsible for the red, pink, and purple tones, while carotenoids contribute to yellow and orange shades. The natural palette of the carnation primarily includes white, various shades of pink ranging from pale to deep rose, and clear reds.
The specific anthocyanins present, pelargonidin and cyanidin, create the vibrant red and magenta colors, with their combination and concentration dictating the final visible hue. Carnations can also naturally produce yellow, cream, and purplish-mauve tones, but the range is inherently limited by the plant’s genetic code.
A key biological limitation is the absence of the necessary enzyme, Flavonoid 3’5′-hydroxylase (F3’5’H), in the carnation’s genetic structure. This enzyme is required to produce delphinidin, the specific anthocyanin that yields true blue and violet colors in other plants. Because of this missing enzyme, carnations cannot naturally produce any blue or black pigment, a trait they share with flowers like roses and chrysanthemums.
Creating Unique and Novel Hues
The desire for colors outside the natural range, such as blue, green, and vibrant purple, has led to two distinct methods for modifying the carnation’s hue. The most common and simple technique is direct dyeing, which is often used to achieve bright, unnatural colors like electric blue or rich green. This process involves cutting the carnation stem and placing it into water mixed with a floral-safe dye.
The flower’s vascular system, specifically the xylem, absorbs the colored water and transports the pigment up to the petals, where it accumulates and changes the color of the bloom. This method is also used to create multicolored or “rainbow” carnations by splitting the stem and placing each section into a different colored solution. The resulting colors are intense but are not permanent, as they are simply a stain rather than a biologically produced pigment.
A more permanent and scientifically complex approach is genetic modification, which successfully introduced violet and lavender shades to the carnation market. Beginning in the 1990s, scientists introduced the Flavonoid 3’5′-hydroxylase gene from other flowers, such as petunias, into the carnation’s DNA. This genetic engineering allowed the carnation to produce the delphinidin pigment, resulting in the development of the ‘Moondust’ series of carnations that express shades of mauve, violet, and purple.
The Symbolic Language of Carnation Colors
The wide palette of the carnation has contributed to a rich tradition of color symbolism known as floriography, where each shade conveys a specific sentiment. Red carnations are universally recognized symbols of deep love and admiration, with darker shades often indicating a more profound passion. Lighter red carnations, in contrast, are often chosen to express simple admiration and affection.
Pink carnations carry a strong association with maternal love and gratitude, a meaning rooted in Christian tradition and the flower’s historical link to Mother’s Day. The holiday’s founder, Anna Jarvis, chose the carnation as its emblem, with pink and red varieties honoring living mothers. White carnations represent purity, innocence, and good luck, making them common choices for weddings and other ceremonies marking new beginnings.
Conversely, certain colors convey a more complicated or negative meaning; for example, yellow carnations traditionally symbolize disappointment, rejection, or disdain. Striped or variegated carnations, which feature multiple colors, are historically associated with regret or refusal. The symbolic language of these flowers allows for nuanced communication through color alone, adding a layer of depth to every bouquet.