Kerry Ferguson — Science + Art Research Series Essay | 2026
Citation: Ferguson, K. (2026). Colour Is Not Decoration: The Science and Art of Botanical Colour. Kerry Ferguson — Science + Art Research Series.
Colour is often the first thing we notice about a plant. The green of a leaf. The red of a berry. The violet of a flower. The yellow of autumn foliage. The extraordinary contrast between a brightly coloured fruit and the vegetation surrounding it.
These colours can become aesthetic experiences. We photograph them, paint them, reproduce them in textiles, extract them as dyes and use them to construct palettes associated with seasons and landscapes.
For the plant, however, colour existed long before aesthetics. Botanical colour emerges from chemistry, cellular structure and interactions with light. Plant pigments participate in photosynthesis, protection from excess radiation, antioxidant processes, attraction, signalling and development. Carotenoids, for example, are essential to photosynthesis and photoprotection as well as contributing yellow, orange and red coloration to many flowers and fruits. Anthocyanins can contribute red, purple and blue coloration and have also been extensively investigated for roles in photoprotection and stress responses.
Some botanical colour does not arise primarily from pigments at all. Microscopic structures can manipulate light and produce structural colour through optical interactions.
The colour we see is therefore not simply a surface treatment.It is evidence of something happening. The Science + Art question becomes: What changes when we stop asking only what colour a plant is and begin asking why that colour exists?
Colour Begins With Light
Colour does not exist independently of light. Visible light contains a range of wavelengths. When light encounters a material, some wavelengths may be absorbed while others are reflected, transmitted or scattered. The colour perceived by the observer emerges from this interaction.
A green leaf does not contain “green” as a simple physical substance. Its pigments and cellular structures interact with incoming light in ways that result in particular wavelengths reaching our eyes.
Change the illumination and the apparent colour changes. A leaf under direct tropical sunlight appears different from the same leaf beneath a rainforest canopy. A flower at midday appears different at dusk. A wet surface can appear darker and more saturated than the same surface when dry. Colour therefore exists within a relationship: light + material + structure + observer. This immediately makes botanical colour interesting for both science and art. Neither discipline can understand colour adequately by treating it as a fixed property.
Why Leaves Are Green
The dominant green of terrestrial vegetation is associated primarily with chlorophylls.
Chlorophyll pigments are central to photosynthesis. They absorb particular portions of visible light and participate in the conversion of light energy into chemical energy.
Green wavelengths are comparatively less strongly absorbed by chlorophyll than some other regions of visible light, contributing to the green appearance of leaves. Yet chlorophyll does far more than create a colour. Its biological importance is energetic.
The green that we associate so strongly with nature is therefore a visual consequence of a molecular system central to the capture of solar energy. Chlorophyll pigments and their associated light-harvesting systems enable plants to respond to varying light environments. This changes the artistic interpretation of green. Green is not simply the colour of foliage. It is the visible presence of a biological relationship with the sun.
Green Is Not One Colour
Walk into a rainforest and the inadequacy of the word green becomes obvious. Young leaves may be pale, bronze or reddish. Mature leaves may range from bright yellow-green to almost blue-green. Glossy leaves reflect light differently from matt leaves. Shade changes hue and saturation. Moisture alters surface reflection. Distance shifts colour through atmosphere. The apparent palette of vegetation is therefore produced by much more than chlorophyll concentration.
Other pigments, surface structures, waxes, leaf thickness, cellular organisation, viewing angle and illumination all contribute. This creates an important artistic principle. A rainforest palette should not begin with a colour chart labelled “green.” It should begin with observation of relationships between greens. Colour becomes spatial and environmental.
Carotenoids: Colour and Protection
Carotenoids are responsible for many of the yellow, orange and red colours found throughout nature. Within photosynthetic tissues they also perform essential biological functions. They participate in light harvesting and, importantly, help protect photosynthetic machinery when light energy exceeds what can safely be used. Carotenoids can dissipate excess energy and participate in protection against photooxidative damage.
The same broad family of compounds can therefore contribute simultaneously to physiology and visual colour. In flowers and fruits, carotenoids can become visually dominant as other pigments are absent or degraded. They contribute to colours associated with attraction and ripening as well as their broader metabolic functions. Yellow and orange are not simply decorative outputs. They arise from compounds participating in the biology of the plant.
Anthocyanins and the Red-Purple Spectrum
Anthocyanins provide another extraordinary botanical colour system. They are water-soluble flavonoid pigments associated with red, purple and blue coloration in many flowers, fruits and vegetative tissues. Their visible colour can change according to molecular structure, pH, co-pigmentation and cellular environment.
For the artist, anthocyanins are immediately attractive because their colours can be intense. For the scientist, their significance extends considerably further.
Research has investigated anthocyanins in relation to environmental stress and photoprotection. In some leaves, anthocyanin accumulation can contribute to protection against excessive light and photooxidative stress. A red leaf therefore may not simply be a green leaf decorated with another pigment.
Its colour may reflect a physiological condition. Colour can be response.
The Chemistry of Changing Colour
Anthocyanins also demonstrate something artists working with natural pigments quickly discover.
Colour is chemically unstable. The apparent colour of an anthocyanin-containing material can depend on its chemical environment. Changes in acidity can alter molecular forms and therefore alter visible colour.
This means botanical colour behaves. It is not simply applied. A dye extracted from plant material may change according to pH, light, temperature, oxidation, mordant, substrate and time. For commercial manufacturing, this instability presents a technical challenge. For artistic practice, it can become part of the work. A colour that shifts is not necessarily a failed colour. It can reveal chemistry. Colour as Environmental Response
Plant colour can change under environmental stress. High light, cold, drought, nutrient conditions and other stresses can influence pigment metabolism. Flavonoid and anthocyanin accumulation has long been associated with plant responses to environmental stress, while carotenoid systems contribute to protection of photosynthetic machinery from excessive light. This means a plant’s colour may contain information about the conditions under which it developed.
Two plants of the same species may not look identical because they did not experience identical environments. Colour becomes another record of place. This connects directly with Pattern as Memory. The landscape remembers through colour as well as through form.
Autumn and the Revelation of Hidden Pigments
Autumn foliage provides one of the most familiar examples of botanical colour transformation. As chlorophyll is degraded during leaf senescence, other pigments can become increasingly visible. Yellow carotenoid-associated colours that were previously masked by chlorophyll may emerge. Red autumn colours can also involve newly synthesised anthocyanins rather than simply exposing pigments that were already present. The biological functions of red autumn coloration have been debated, with research examining hypotheses including photoprotection during nutrient resorption.
What we experience as an extraordinary seasonal spectacle is therefore the visible manifestation of physiological transformation. Autumn colour is not paint appearing on the leaf. It is metabolism changing.
Colour and Attraction
Flowers and fruits demonstrate another biological dimension of colour. Colour can participate in relationships between plants and animals. Flowering plants may depend upon pollinators. Fruits may depend upon animals to disperse seeds. Pigments help create visual signals within these relationships. Carotenoids and anthocyanins can contribute conspicuous colours in reproductive tissues, while their roles coexist with scent, morphology, timing and reward.
The colour of a flower is therefore not meaningful in isolation. Its significance partly depends upon the visual system of the organism encountering it. Colour belongs to the receiver as much as to the object.
We Do Not See What Every Pollinator Sees
Our colour perception represents only one way of seeing the world. Other organisms possess different photoreceptor systems and can respond to wavelengths and visual patterns that humans perceive differently or may not perceive at all.
A flower that appears visually simple to us may present a different visual signal to a pollinator. This is an important challenge to artistic assumptions.
When we reproduce a flower according to our vision, we are not reproducing the complete biological signal. We are producing one species-specific interpretation. The botanical world does not exist visually for us alone.
The Flower as Multisensory Design
Colour rarely operates independently in a flower. Scent, morphology, nectar, texture and timing can all contribute to interaction with pollinators. A flower is therefore a multisensory biological structure.
We often separate its characteristics because our industries require separation. We extract scent for perfume, pigment for colour, form for pattern and bioactive compounds for ingredients. The plant combines them.
This suggests a useful Science + Art principle. When botanical attributes are reunited conceptually, the subject becomes richer. A colour can be investigated alongside its chemistry, scent, structure and ecological function.
Fruit Colour and Time
Fruit colour often changes through ripening. Green can disappear. Yellow, orange, red, purple or other colours become increasingly visible. These colour changes can coincide with changes in texture, aroma, acidity and sugar concentration. The fruit is changing both chemically and visually. Colour therefore becomes temporal information. It tells potential consumers something about developmental state. Fruit colour has become so culturally familiar that we often read these signals without consciously thinking about them. We know what ripe looks like. The visual system has become part of agricultural and culinary knowledge.
Colour Can Warn
Attraction is only one biological role associated with conspicuous colour. Across the living world, colour can also contribute to warning, camouflage and deception. Plants participate in some of these relationships through combinations of pigmentation, form and mimicry.
This complicates the idea that beautiful colour exists primarily to attract. A conspicuous surface can have very different ecological consequences depending upon context.
The same red that attracts one organism might warn another. Colour has no universal meaning. It operates within relationships.
Structural Colour
Not all colour depends primarily upon pigment. Some biological surfaces create colour through microscopic or nanoscale structures that interact physically with light.
These structures can produce effects such as iridescence, in which apparent colour changes with viewing or illumination angle. Structural colour has been documented across animals and plants, and research into its cellular basis in plants has begun identifying how specialised structures can generate optical effects.
This is a profound concept for art and materials. The colour may not be contained in a coloured chemical at all. It can emerge from structure.
When Structure Becomes Colour
Structural colour collapses the traditional separation between form and colour. Usually we imagine that an object has a structure and then possesses a colour. In structurally coloured materials, the physical architecture itself contributes directly to the optical effect. Change the structure and the colour changes.
This has inspired extensive research into photonic and biomimetic materials because structural colour can potentially provide optical effects without conventional pigment chemistry. For the artist, the implication is equally interesting. Colour can be constructed. Texture, layering and surface geometry can become part of the palette.
Iridescence and Movement
Pigment colour can remain relatively stable as the observer moves. Structural colour can behave differently. A surface may shift from blue to green or violet according to angle. The viewer becomes part of the colour event. Movement changes perception.
This creates a very different relationship between object and audience. The artwork is not entirely visible from one position. Colour unfolds through movement.
For textiles, reflective fibres, metallic thread, layered transparent materials and interference effects can create similar experiences without literally reproducing biological structural colour.
The principle is more important than imitation. Colour can depend upon how the observer moves through light.
Botanical Colour and Surface
The surface of a plant affects how its colour appears. Gloss, wax, hair, texture and cellular structure all influence reflection and scattering. A waxy leaf can produce sharp highlights. A hairy leaf may appear softer or greyer. Water changes surface reflection. Damage can expose tissues with different colours. This means the colour sample taken from a photograph can never fully reproduce the experience of the living surface.
Digital colour codes remove texture, illumination and angle. They reduce a complex optical event to a numerical value. That reduction is useful. But it is incomplete.
The Problem with the Colour Palette
Designers routinely derive palettes from landscapes. Five or six colours are sampled from an image and presented as the visual identity of a place. This can be useful as an organisational tool.
But a landscape is not a palette. Its colours change continuously with weather, light, distance, moisture, season and biological activity. A Daintree palette selected during direct sunlight may bear little resemblance to the same landscape during rain. Molong in summer differs from Molong after rainfall. Celestial Vespers exists precisely because the same landscape changes colour as daylight disappears.
A more sophisticated colour system therefore records relationships and transformations, not just swatches.
Colour Through Time
This is particularly important for the Dangerous Beauty collections. Colour can be organised temporally. A palette can record morning, midday, afternoon and twilight. It can record growth, maturity and senescence. It can move from drought into rainfall. It can record flowering and fruiting. The collection then contains a sequence. Colour becomes narrative. The viewer encounters not simply a place but change within that place.
Celestial Vespers and Unstable Colour
Celestial Vespers offers the clearest example. Twilight colours are inherently unstable.
The spectrum and intensity of illumination shift continuously as the sun moves below the horizon. Atmospheric conditions modify scattering. Cloud, dust, moisture and geography alter the result. Objects that appeared colourful in daylight can become silhouettes. The same pigment on a textile changes appearance as ambient light changes. This means Celestial Vespers should not be designed around one definitive twilight palette. Its subject is the failure of colour to remain still.
Colour and Memory
Colour also operates psychologically and culturally. A particular green can evoke rainforest. Ochre can evoke earth. Deep blue can suggest evening. Gold can suggest sacredness, value or light. These associations do not arise from plant physiology. They arise from human experience.
Science and art therefore encounter colour differently. Science asks about wavelength, pigment, molecular structure and function. Art also asks about memory. The same colour can be simultaneously physical and symbolic. Neither explanation cancels the other.
Botanical Pigments as Human Materials
Humans have extracted colour from plants for thousands of years. Leaves, roots, bark, fruits and flowers have provided dyes and pigments for textiles, food, cosmetics and art. When a pigment is removed from a living plant and placed onto fabric, it enters a radically different environment. Its biological function disappears. Its chemistry remains.
Light, oxygen, pH, fibre chemistry and washing can then determine its stability.
A pigment that functioned effectively for the lifetime of a flower may perform poorly as a textile dye expected to remain unchanged for decades. This distinction is important. Biological success and material permanence are not the same thing.
The Artist’s Desire for Permanence
Artists often want colours to remain stable. Museums evaluate lightfastness. Textiles are expected not to fade. Pigments are selected partly according to permanence. But botanical colour evolved within organisms that themselves are temporary. A flower need not remain colourful for fifty years. Its colour needs to function during the biological period for which it is required.
This creates an interesting tension between nature and art conservation. When we extract a natural pigment and demand permanence, we are imposing a human timescale upon chemistry that evolved for another purpose. Perhaps sometimes fading can become part of the artistic concept.
Fading as Information
A fading colour usually indicates loss. The artwork is deteriorating. The original appearance is disappearing. Yet fading can also reveal the relationship between material and environment. Light has acted. Oxidation has occurred. Time has passed. For work concerned with memory, landscape and biological change, these transformations can be conceptually meaningful.
This does not mean conservation should be abandoned Rather, artists can decide deliberately which changes should be resisted and which can be accepted as part of the work. Material impermanence becomes a choice rather than an accident.
Colour as Experimental Material
The laboratory and studio again begin to resemble one another. A scientist can investigate how pH changes anthocyanin colour. An artist can conduct a series of material experiments using changing acidity. A scientist measures light degradation. An artist exposes samples to controlled light. A scientist evaluates pigment concentration. An artist changes dye loading.
The objectives differ. One seeks reproducible chemical understanding. The other seeks visual and material possibilities. But the process begins with the same action: change one condition and observe what happens.
Chromatography Separates Colour
Botanical extracts that appear to possess a single colour can contain several pigments or related compounds. Chromatographic separation reveals this hidden diversity. The apparently uniform red of a plant extract can resolve into multiple chemical constituents.
This offers another powerful Science + Art idea. What appears visually singular may be chemically plural. A colour is often a mixture. A landscape is often a mixture. A memory is often a mixture. Separation reveals complexity that perception compressed.
From HPLC to Textile
Again, the objective should not be simply to print chromatograms onto fabric.
The more interesting translation is conceptual.
Suppose analytical chemistry reveals several anthocyanins contributing to a colour.
An artwork might be constructed from overlapping translucent colour layers that together produce the final hue.
Separate them and the colour changes. Combine them and another visual identity emerges. The artwork then explores the principle of chemical mixture through material layering. Scientific information affects structure rather than becoming illustration.
Colour Families and Chemical Families
Pigment chemistry also allows artistic collections to be organised through chemical relationships. Anthocyanin-associated colours can generate one family. Carotenoid-associated colours another. Chlorophyll another.
The objective is not to create a scientifically exact colour chart, because botanical appearance depends on far more than compound family alone. Instead, chemical classification can provide an intellectual structure for artistic variation. Colour families become connected to biological functions. `The palette acquires a reason for existing.
The Beauty of Protection
Photoprotection reveals one of the most interesting intersections between function and beauty. Carotenoids help protect photosynthetic systems against excessive light energy. Anthocyanins in some tissues can contribute to screening and photoprotective responses. The compounds performing these functions can also produce colours we find beautiful.
Protection becomes visible. This is a recurring theme in the Science + Art series.
The structures and chemicals humans admire frequently emerged because they did something useful to another organism. Beauty can be an accidental human interpretation of biological function.
Dangerous Beauty in Colour
Colour can also reveal the darker side of botanical relationships. A brightly coloured fruit may attract an animal. A conspicuous flower may manipulate pollinator attention.
Pigmentation can respond to stress. Toxic plants can be visually beautiful. Colour provides no guarantee of safety.
The aesthetic and biological meanings of a botanical surface may be completely different. We see beauty while the plant is solving another problem. Designing with Colour Rather Than Choosing Colour Conventional design often treats colour as a late decision.
The form is created and a palette is applied. Nature suggests another approach. Colour can be integrated with function, material, environment and time. In a Science + Art practice, colour selection can therefore begin with questions. What process produced this colour? Does it change? What does it interact with? Does it attract? Protect? Signal? Disappear? Depend upon light? Depend upon structure?
The answer can determine not only the hue but the material and method used to produce it. Colour becomes part of the design logic. A Framework for Botanical Colour Research A botanical colour project can begin with a specific organism, pigment or environment.
Scientific research should first establish what produces the colour and what is known about its biological role.
The artist can then investigate the visual consequences. Colour should be recorded under different illumination and environmental conditions rather than sampled only once. Where appropriate, the chemistry can be experimentally explored through pH, concentration, oxidation, light or material interaction. Structural effects should be distinguished from pigment effects.
The final work can then translate the behaviour of colour, not simply reproduce its appearance. This creates a much richer relationship between botanical science and artistic practice.
Beyond Botanical Colour
The subject also leads naturally towards biomimicry. Structural colour has already inspired research into photonic materials that create colour through micro- and nanoscale organisation rather than conventional pigments.
Nature can inspire design at several levels. We can copy the colour. We can copy the structure producing the colour. Or we can understand the physical principle and develop an entirely different material that uses the same strategy. The deeper we move, the less literal the imitation becomes.
Conclusion
Botanical colour is easy to admire. It is considerably more interesting to understand.
The green of a leaf begins with light and photosynthetic pigments. Yellow and orange can emerge through carotenoids that also participate in photoprotection and plant signalling. Red, purple and blue can emerge through anthocyanins whose chemistry responds to cellular environment and whose accumulation can be associated with stress and photoprotection. Some colours emerge not principally from pigment chemistry but from microscopic structures that manipulate light.
Flowers use colour within relationships with pollinators. Fruits change colour as it develops. Leaves change colour through senescence. Environmental stress alters pigmentation.
Light changes perception. Time changes chemistry. The artist therefore encounters something far richer than a palette. Colour has a history. A chemistry, a function, an environment, a timescale and an observer.
Science allows us to understand why botanical colours exist and how they behave. Art allows us to explore what happens when those explanations enter perception and material practice.
The result is not a scientific illustration of colour. Nor is it colour selected simply because it is attractive. It is colour understood as evidence of a living process. This is why botanical colour is not decoration. A red leaf may be protecting itself. A yellow petal may be participating in attraction. A green surface is capturing energy. An iridescent structure is manipulating light. A fading pigment is revealing chemistry and time.
The natural world does not apply colour after designing the object. Colour is part of the system.
Research Context
Colour Is Not Decoration forms part of Kerry Ferguson’s Science + Art Research Series and develops themes established in The Intelligence of Plants, Plants as Chemical Engineers and The Chemical Language of Plants.
The essay explores botanical colour through plant physiology, pigment chemistry, ecology, optics, environmental response and perception. It also establishes a foundation for artistic experimentation with botanical dyes, pigments, light, textile processes, structural colour, material ageing and changing colour.
The research provides another intersection between Botanical Innovations’ scientific investigation of bioactive compounds including anthocyanins, flavonoids and carotenoid-related systems and Dangerous Beauty’s exploration of colour, textiles, landscape and changing light.
Selected References
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- Demmig-Adams, B., Gilmore, A.M. & Adams, W.W. III. (1996). Carotenoids 3: In vivo function of carotenoids in higher plants. FASEB Journal, 10, 403–412.
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- Mandelbrot, B.B. (1982). The Fractal Geometry of Nature. W.H. Freeman.
- Lee, D.W. (2007). Nature’s Palette: The Science of Plant Color. University of Chicago Press.
- Gage, J. (1999). Color and Meaning: Art, Science and Symbolism. University of California Press.