Chrysanthemums (mums) are globally popular flowers known for their diverse bloom shapes and long-lasting color. Native to East Asia and Northeastern Europe, they are a mainstay in the floral industry and gardens, especially during autumn. Their extensive range of colors is a primary reason for their widespread appeal and cultivation. This variety results from centuries of breeding efforts focused on the flower’s natural pigment composition.
The Extensive Natural Color Palette
The chrysanthemum’s color spectrum is determined by two classes of pigments: carotenoids and anthocyanins. Carotenoids produce warm colors, while anthocyanins create cooler shades like red, pink, and purple. The combination or absence of these compounds in the ray florets (petals) dictates the final hue.
White chrysanthemums result from the absence of both major pigment types, creating a pure, achromatic appearance that sometimes shifts to a creamy off-white. Yellows and golds are produced solely by carotenoids, ranging from soft, pale lemon to intense, deep gold and vibrant orange. When orange flowers accumulate anthocyanins, the resulting shades are the coppery, earthy colors known as bronze.
The red series is defined by high concentrations of anthocyanins, spanning from bright scarlet to rich, dark burgundy and deep crimson hues. Pink varieties contain lower levels of anthocyanins, creating a range from soft, blush pastels to striking, vibrant magenta. Purple and lavender shades also stem from anthocyanin accumulation, with the final color influenced by the flower’s internal acidity. This natural palette provides the foundation for cultivated chrysanthemum varieties.
Rare Hues and Genetic Limitations
While chrysanthemums boast many colors, their natural chemistry limits the production of certain shades, notably true blue and black. The inability to produce blue pigment stems from lacking the enzyme flavonoid 3’5′-hydroxylase (F3’5’H). This enzyme is necessary to create delphinidin, the main blue-coloring anthocyanin found in other flowers. Without this enzyme, chrysanthemums cannot synthesize a pure blue hue. Black shades are also genetically absent, as achieving a true black requires an extremely high concentration of dark pigments that the flower cannot accumulate.
Some rare natural colors do exist, such as the unusual green chrysanthemum, where the petals retain chlorophyll. To bypass genetic limitations for colors like blue, commercial florists often use artificial methods. White cut chrysanthemums can be dyed by placing their stems in water mixed with colored pigments, allowing the dye to be drawn up into the petals through the vascular system. This process satisfies the market demand for colors that cannot be achieved through traditional breeding.
Patterns, Blends, and Bi-Color Variations
The diversity of chrysanthemum colors is expanded by how pigments are distributed across the individual flower. Bi-colored varieties feature petals with two distinctly different colors, often contrasting between the base and the tip. For example, the “Matchsticks” variety has bright yellow bases and red tips, creating a striking visual effect.
Other variations include striping or streaking, where lines of a secondary color run through the main petal, leading to a mottled or flecked appearance. Blends and shading introduce a gradual transition of color across the petal, such as a darker center fading toward a lighter edge, creating an ombre effect. This blending increases the perceived color range beyond the solid base colors, offering cultivars like ‘Annie Girl,’ which presents a peach interior that transitions into a pastel pink and sometimes a hint of lavender.