The genus Camellia is a collection of evergreen shrubs and small trees native to East Asia, primarily valued for their glossy foliage and striking winter flowers. These plants, which include the tea-producing species Camellia sinensis, have been cultivated for centuries as ornamental plants. With over 26,000 registered cultivars, the camellia flower provides a broad spectrum of colors and forms, often blooming when most other plants are dormant.
The Dominant Color Palette
The most common and widely hybridized camellia colors span the range from pure white to deep red, with numerous shades of pink in between. White varieties are highly sought after, appearing as pristine snow-white or a slightly warmer, creamy ivory shade. The absence of pigment allows the petals to showcase the flower’s form and texture with stark clarity.
Pink is arguably the most expansive color class, encompassing a delicate range from the faintest blush to saturated, deep rose or salmon tones. These varying pinks are influenced by the concentration of red-producing pigments. Red camellias offer an equally dramatic display, ranging from brilliant scarlet and fiery crimson to the deepest, almost black shades of burgundy.
A significant feature that adds complexity is variegation, where a single flower displays multiple colors in distinct patterns. This color breaking often presents as stripes, blotches, or mottling of white on a pink or red background. The cultivar ‘Lady Vansittart,’ for example, is known for its cotton candy pink blooms streaked with bright red.
Absent and Rare Color Varieties
While the camellia palette is rich in reds, pinks, and whites, it is notable for the absence of certain primary colors, particularly true blue and purple shades. The Camellia genus does not possess the necessary enzymes to complete the biochemical pathway for producing blue pigments. Although some red cultivars may exhibit a purplish cast as the bloom ages, these are not considered true purple flowers.
The yellow camellia was historically considered a rare exception until the discovery of specific species from southern China and Vietnam. The most significant of these is Camellia nitidissima, formerly known as Camellia chrysantha, often called the “Golden Camellia.” These rare yellow species were not widely available until the 1980s.
The color of these yellow camellias is typically a pale lemon or rich gold, not the vibrant, sunflower-yellow found in some other plant families. Hybridizers have used these species to introduce the yellow trait into ornamental cultivars. This effort often results in flowers with creamy white outer petals and a soft yellow center.
The Science Behind Camellia Pigmentation
The wide array of camellia colors is determined by the presence and concentration of two primary classes of chemical compounds: anthocyanins and carotenoids. Anthocyanins are water-soluble pigments responsible for nearly all the red, pink, and purplish tones. The shades of red and pink are directly related to the amount of anthocyanin present, with higher concentrations resulting in deep crimson or burgundy colors.
Cyanidin glycosides are the main type of anthocyanin found in red and pink camellias. The final hue can be subtly modulated by the acidity (pH) within the cell vacuoles of the petal tissue. A lower, more acidic pH favors brighter red tones, while a slightly higher pH can push the color toward a purplish-red. The genetic inability to produce the enzyme required to synthesize delphinidin, a precursor to blue pigment, explains why true blue and violet camellias do not naturally exist.
Yellow coloration in species like C. nitidissima is primarily due to a combination of two pigment classes. Carotenoids, specifically xanthophylls, provide a distinct yellow color. Certain yellow-colored flavonoids, such as quercetin glycosides, also contribute to the golden hue. Variegation, the mixed color patterns on petals, is often caused by a lack of pigment production in certain cell lines, either due to a genetic mutation or a benign virus that disrupts the color pathway in patches of tissue.