4. BIO CHROMES¶
"colour is all around us. It's something we often take for granted, because it permeates our environment everywhere we go. But rarely do we stop to consider: Where does color come from? What does it actually look like in its natural form? & what kind of relationship do we really have with color — culturally, historically, or locally?" - Cecilia Raspanti
This week, we’re diving into the world of natural colours — tones derived from minerals, plants, microorganisms , fungi or animal-based sources.
When working with natural dyes, it’s essential to also consider the material being dyed. Natural fibers react differently to dyes and require specific mordanting and dyeing methods.
PLANT-BASED FIBERS¶
These fibers are made of cellulose and come from seeds, leaves, stems, bark, or wood. Because cellulose doesn’t always bond well with mordants, tannins are often used first to improve dye absorption.
MAN MADE FIBERS¶
These are man-made fibers derived from plant cellulose through chemical extraction and spinning. Though not found in nature as fibers, they behave similarly to plant fibers when dyed.
ANIMAL FIBERS¶
Made mostly of protein, they are generally easy to dye and produce deep, vibrant colors. Proteins react well with acids, alkalis, and mordants, allowing strong dye fixation.
But before we go straight into recipes, techniques or material experiments, let’s take a small step back & ask: what does “BioChromes” actually mean?
We often speak casually about “natural dyes” — but “BioChromes” is a term that invites us to think deeper. It’s made up of two words: “bio” (life) & “chrome” (colour).
Together, they describe colour that is alive. Colour that isn’t static or fixed, but changeable, reactive & always in flux. These are colours that come from natural sources — but also colours that carry a sense of process. They shift, fade, transform. They react to light, time, touch.
When we explore natural dyes, it’s not only about aesthetics or surface colour. It’s about material awareness, ecological cycles & cultural narratives. Dyeing is a practice with deep roots — & at the same time, a space for innovation, sustainability & experimentation.
We’ll also look at how traditional knowledge, heritage materials & older recipes can inform contemporary design. Sometimes, taking a small step back helps us move more meaningfully forward — into futures that are already rooted in possibility.
The world is different! depending on where you are — & how that difference shows up in colour. What grows in Mexico might not grow in Germany. Or it might grow in a completely different form. What’s local & normal for you might be rare or new to someone else. That’s the beauty of natural colour — it doesn’t just show us what’s possible. It also reminds us where we come from. &maybe even where we want to go.
50 SHADES OF GREIGE¶
"Every form of creation begins with color, material, & surface – & with understanding how they affect us."
Colours had always fascinated me — even if that might be hard to believe today. If you’ve seen my wardrobe or my apartment, you’d probably assume I’ve lived half my life in nothing but shades of grey, with the occasional beige or silver. Yet there were times when I wore nothing but neon.
I’ve always been drawn to colour & materials. For me, color is never just decoration – it’s material, emotion, & interaction. Grey & beige, often dismissed as boring — to me, they’re full of depth. Grey is endlessly combinable, it works with every other colour. Beige, on the other hand, is tricky — every slight undertone changes how it behaves.
I take great pleasure in proving, again & again, that these so-called “neutral” colours are anything but boring!
When I discovered the specialization COLOUR DESIGN, my first thought was: “Where’s the catch?” It felt too good to be true. Every part of it excited me. When the task was to create 15 samples, I made 200 — & couldn’t stop.
Colour Design is a unique study field in Germany. It deals with CMF – Color, Material, Finish – & includes trend research, which I believe should be part of every design education! After all, every kind of design is shaped through colour, material, & their interaction. In his book haptic VISUALS TIMO RIEKE shows how the same object can feel heavier or softer to us, depending on its colour — rose or grey, for example.
Understanding trends is essential for designers. We live in the 21st century — often we don’t need to reinvent the wheel, but we can combine meaningfully: new materials with traditional crafts, forgotten materials with innovative techniques. That’s how we create something truly new. & to design the future, we must first understand the present — & know the patterns of the past.
PURBLE ISN'T A REAL COLOUR¶
Did you know that purple isn’t actually a real color?
to break it down: Inside our eyes, we have rods & cones. When light enters through the iris, it hits the back of the eye, where the light rays are processed. The rods help us see light & dark, while the cones are responsible for detecting red, green & blue wavelengths. When all 3 types of cones are activated, we perceive brightness. When none are activated, we see darkness. Our visible spectrum lies between ultraviolet & infrared light. We can perceive wavelengths from red to blue — red has the longest, slowest waves, blue has the shortest, fastest ones. Green lies right in the middle.
So when light hits the eye in a way that stimulates both the red & blue cones, but not the green ones, the brain interprets this as purple. Which means: purple is basically the absence of green.
INSPIRING BOOKS¶
- WILD COLOR - The Complete Guide to Making and Using Natural dyes: Jenny Dean/ Karen Diadick Casselman
VIDEOS¶
- "So habt ihr Farben noch nie gesehen" / You've never seen colors like this before - MAITHINK X
REFERENCES & INSPIRATION¶
BIO CHROMES¶
BIOCHROMES ARCHIVES – A Living Archive of Natural Color
The BioChromes Archive is part of the open research series Archives of the Future, initiated by designer & researcher Cecilia Raspanti. Since 2010, she has been collecting & documenting natural, bio-based dyes & materials — with the aim of rethinking sustainable design: local, compostable & circular.
What began as a spontaneous dyeing reaction after a storm has grown into an evolving, living archive of over 200 samples — complemented by photographs, material studies & colour systems. BioChromes treats colour not just as pigment, but as an active element of material & meaning.
BioChromes represents a future-oriented understanding of colour — as a connection between nature, research & social responsibility.
LIVING LIBRARY¶
As part of my master’s thesis MUSE LAB– an open, mobile space for multisensory material & design exploration – I conducted field research across Europe, visiting labs, exhibitions & workshops. One of these stops was the BIO DESIGN LAB in Karlsruhe, Germany.
Since April 2024, the LIVING LIBRARY has been growing there — a temporary, evolving material archive dedicated to locally sourced, biodegradable raw materials & circular design. Over a period of two years, the project at the Bio Design Lab explores experimental production methods & sustainable making. Materials are collected, developed, activated — and eventually returned to the soil. The process is digitally documented & will be published as an open-access resource. The Living Library bridges research & practice, design & nature — and serves as an inspiring example of future-oriented material culture.
Coordination: Julia Ihls
Also good to know: The BIO DESIGN LAB Karlsruhe is also working on another project — THE ARCHIVE OF ARCHIVES The Archive of (other) Archives is a growing collection of material libraries from around the world – an inspiring source for sustainable materials, recipes, labs & making techniques.
HERMI COLOURS¶
Just Around the Corner
Lisa Hermann’s studio is literally, just around the corner – only a street away from my apartment. Until recently, she even shared a storefront with one of my closest friends.
Since 2019, she has been developing vegan watercolor paints & plant-based dye techniques — a craft that grew from a personal hobby into her daily practice. In her studio in Hanover, she experiments with natural pigments, hand-dyes both new & vintage textiles, & creates sustainable art materials. Her work blends traditional color knowledge with a deeper cultural awareness & a commitment to ecological design. In her workshops, she shares not only technical skills but also the historical & social dimensions of natural color — showing how rich, symbolic, & meaningful color can truly be.
INDIGO REBELL¶
When it comes to natural dyeing, Petra Hassan is not to be overlooked. She lives between Hannover and Morocco and specializes in indigo dyeing — particularly in the Japanese Shibori technique. Her work bridges traditional dyeing knowledge with contemporary design sensibilities. Through workshops, craft fairs, and collaborations, she shares her expertise in indigo, textiles, and sustainable dye practices.
AGRO ARTE¶
Agro Arte is a social & ecological textile project based in the Cauca region of Colombia (Vereda La Muyunga – El Tambo). Their work bridges traditional weaving practices with a holistic & sustainable approach — from cultivating silkworms & processing cocoons to hand-spun yarns, woven fabrics, & finished textile pieces. At its core, Agro Arte celebrates the knowledge, skill, & earth-connected artistry of its community of weavers.
As part of an excursion with the Master’s program in Colour Design @ HAWK University University of Applied Sciences & Arts in Hildesheim & the IIT & in cooperation with Claudia Gómez MejíaIIT Bogota, we had the opportunity to participate in a workshop led by Agro Arte on natural dyeing — especially using coca leaves.
This hands-on experience offered deep insights into plant-based color processes & the cultural significance of natural materials.
In exchange, we — the participating students — facilitated a workshop on trend scouting, sharing approaches to observing, analyzing, & interpreting aesthetic tendencies within sustainable design contexts.
Institute International Trendscouting (IIT)¶
IIT HAWK University of Applied Sciences & Arts in Hildesheim is a European research & consulting institute focusing on color & surface design. IIT conducts global color & material research with social & design relevance, analyzing visual & cultural trends to identify future developments. Through systematic image & data analysis, the institute explores shifts in color, material, & surface aesthetics, developing tools & strategies that help designers, architects, & companies make informed, design-driven decisions.
ASSIGNMENT - BIO CHROMES¶
PRESENTATION INSPIRATION¶
Material Samples, Documentation & Presentation
Creating material samples is not only about producing the samples themselves but also about their documentation, archiving & presentation. I have considered how to store, organize & display the textile samples in a way that highlights both their material qualities & the creative process behind them.
IMPLEMENTATION / STEP BY STEP¶
Process & Research
To begin, I browsed through the book Wild Colours by Jenny Dean (which I highly recommend). What I particularly appreciate about this book is its clear structure & the way it allows you to see at a glance where each plant originates in the world & which colours can be obtained—depending on the mordants—from its
leaves, flowers, fruits, bark & roots.¶
Plant Selection
I focused on plants that are native to many regions of the world & are often considered “weeds.”
In particular, I was interested in species that can produce
yellow, grey & green tones,¶
as these hues offer a subtle yet versatile colour palette for natural dyeing experiments.
WILD COLOURS¶
Tagetes erecta – The Upright Marigold¶
Having arrived in Mexico — & with one of the most important traditional holidays just around the corner — I decided to focus on a very specific plant: Tagetes erecta, commonly known as the Upright Marigold.
This vibrant orange-yellow flower plays a central role in Mexican remembrance culture: it is cultivated in large quantities to adorn altars & symbolically guide the souls of the departed. Its vivid color & characteristic scent make it not only culturally significant but also an exciting subject for dyeing experiments & material-based research.
What I’ve Planned¶
In this assignment, beyond experimenting with natural dyes, my main focus is on the presentation & documentation of the results:
Material Samples¶
I plan to create a series of textile samples using natural dyeing techniques with Tagetes erecta (Upright Marigold). The aim is to explore: - Color range - Texture variation - Material behavior on different types of fabric
Documentation Strategy¶
Each sample will be documented in detail, covering: - Ingredients used - Dyeing process - Timing - Environmental conditions
Archiving & Presentation¶
I am developing a modular folder or booklet system for: - Organizing the samples - Presenting them visually alongside their documentation - Highlighting both outcome & process
Cultural Context: Cempasúchil¶
Cempasúchil, known as the Mexican Marigold (Tagetes erecta), is also called the
Flower of the Dead.¶
It holds a deeply rooted place in Mexico’s cultural & spiritual landscape — particularly during the Día de Muertos (Day of the Dead) celebrations.
During this time, the bright orange & yellow blossoms are used in abundance to decorate altars, pathways, & offerings. Their vibrant color & distinctive scent are believed to guide the souls of the departed back to the world of the living, lighting their way home.
- Botanical Name: Tagetes erecta (Mexican Marigold)
- Etymology: The name Cempasúchil originates from the Nahuatl word zempoalxochitl, meaning “twenty flowers” — a poetic reference to the flower’s many layered petals.
- Cultural Meaning: Beyond its beauty, the plant embodies the connection between life & death, presence & memory — serving as both a symbol of remembrance & renewal.
- Color Symbolism: The luminous orange-yellow tones represent light, vitality, & warmth. They are thought to welcome returning souls with brightness & affection, bridging the worlds of the living & the dead through colour & scent.
Before You Start¶
Before beginning & dyeing experiment, take time to prepare the setup & documentation — it will make your results repeatable & meaningful.
| Tip | Description |
|---|---|
| Make notes | Write down every step: dates, fiber weights, water amounts, temperatures, & modifiers. |
| Photograph your process | Capture each stage — from raw materials to final colors. Even imperfect shots help track results later. |
| Label everything | Mark your pots, dye baths, jars, & fabrics with waterproof tags. |
| Track your timing | Note when each process starts & ends (washing, mordanting, dyeing, cooling). |
| Keep samples | Staple or tape dried swatches into your notebook with labels: fiber type / dye bath / modifier / duration. |
| Stay organized | Use one clean workspace per fiber type (cotton / wool). Keep materials separate but process in parallel. |
| Be mindful | Observe how water color, temperature, & even smell change — these are clues to the chemistry of color. |
Introduction¶
Natural dyeing with plant-based colors & natural fibers consists of 3 - 4 essential steps:
- Washing (cleaning)
- Mordanting (preparing)
- Dyeing
- & optionally Modifying (adjusting the hue).
Each of these stages is crucial to create a durable & harmonious bond between the fiber & the dye. It is important to note that - plant-based fibers (such as cotton, linen, hemp) & - animal fibers (such as wool, silk) are structurally different & therefore react differently during the dyeing process.
As i mentioned: Plant fibers are made of cellulose & usually require stronger mordants or protein bridges (for example, soy milk or tannins) to help the colour adhere more effectively.
Animal fibers, on the other hand, are made of protein (keratin, silk), which naturally attracts dyes more easily but is also more sensitive to heat & alkaline substances.
For my assignment, I decided to work with 2 fiber types:
- Cotton (plant-based) &
- Wool (animal-based)
— each in two forms: as woven textile & as yarn/fiber.
My goal was to observe & compare the differences in preparation, dye absorption, & colour result.
( In practice, I worked with 75 g of cotton & 100 g of wool. To make the recipes clearer & easier to scale, I standardized all proportions & measurements to 100 g of fiber weight.)
1. Washing¶
| Step | Cotton 100 g | Wool 100 g |
|---|---|---|
| Water | 300 mL | 300 mL |
| Additive | 1 g baking soda (NaHCO₃) | 1 drop mild soap / SLES 28% |
| Temperature | 70–80 °C | 40 °C (lukewarm) |
| Time | 30–45 min simmer | 15 min soak, minimal movement |
| Note | Just cover fabric, don’t overfill | Rinse gently, keep slightly damp |
2. Mordanting¶
| Step | Cotton 100 g | Wool 100 g |
|---|---|---|
| Water | 400 mL | 400 mL |
| Mordant | 10 g alum | 10 g alum + 5 g cream of tartar |
| Temperature | 80–85 °C | 70–75 °C |
| Time | 45–60 min | 45–60 min |
| Note | Fully immerse cotton, stir occasionally | Let wool sit still, do not agitate |
3. Dyeing – Cempasúchil (Tagetes erecta)¶
| Bath | Cotton 100 g | Wool 100 g | Result |
|---|---|---|---|
| Bath A – Strong | 75 g dried petals + 400 mL water | 75 g dried petals + 400 mL water | Deep golden orange |
| Bath B – Light | 35 g petals + 300 mL water or 150 mL from Bath A + 150 mL water |
same ratio | Light sunflower yellow |
| Temp / Time | 80–90 °C · 45 min | 70–80 °C · 45 min | — |
| Aftercare | Cool in bath → rinse → dry in shade | same | — |
4. Modifiers (optional)¶
Observation & Adjustment¶
Since the colour results from both dye baths (A & B) turned out surprisingly similar,I decided to place the textiles samples from Bath B into a vinegar modifier bath. The goal was to brighten & clarify the tones — achieving a slightly clearer, more luminous yellow hue.
Modifier Bath¶
A modifier bath is a short, optional step after dyeing, used to adjust the shade or tone of your already dyed textiles. It’s essentially the fine-tuning of your color — you use it to brighten, warm, cool, or deepen tones depending on the pH or additive you apply.
What happens chemically?¶
Natural pigments are pH-sensitive — even small changes in acidity or alkalinity can visibly shift the color:
| pH Range | Agent / Medium | Effect on Color |
|---|---|---|
| Acidic (pH < 7) | Vinegar, lemon juice | Lighter, clearer, sometimes pinkish |
| Neutral (pH ≈ 7) | Distilled water | No change |
| Basic (pH > 7) | Baking soda, washing soda | Warmer, deeper, golden or brownish |
This pH sensitivity is especially visible in plant-based dyes such as Cempasúchil, Cochineal, Hibiscus, or Red cabbage.
Modifier Bath – Step-by-Step¶
| Step | Procedure |
|---|---|
| 1. After dyeing | Remove fabric from dye bath, rinse briefly. |
| 2. Prepare modifier bath | Add ~500 mL of fresh water to a clean glass or pot. |
| 3. Add modifier | According to desired effect (see table below). |
| 4. Submerge fabric | Let sit for 5–10 minutes, stir gently. |
| 5. Observe color | Reaction happens fast — check frequently. |
| 6. Remove & rinse | Rinse in clean water, dry in shade. |
Common Modifiers¶
| Modifier | Amount (per 500 mL water) | pH | Effect | Fiber |
|---|---|---|---|---|
| Vinegar (5%) | ½–1 tsp | mildly acidic | brightens, clears tone | wool & cotton |
| Baking soda (NaHCO₃) | pinch (~0.3 g) | mildly basic | warmer, golden tone | cotton |
| Iron water (iron acetate) | 1–2 drops | slightly acidic | darkens, olive-green hue | both |
| Lemon juice | 1 tsp | acidic | lighter, slightly redder tones | both |
Example: Cempasúchil Yellow¶
After dyeing: In vinegar bath → tone becomes lighter, clearer, more sun-yellow In baking soda bath → tone turns warmer, golden-orange In iron bath → tone deepens toward olive-yellow
Important¶
- Modifier baths are optional.
- Always test on a small sample first.
- Do not soak too long — colors may dull.
- Use only one modifier per fabric piece.
Mini Color Card – Cempasúchil (Tagetes erecta) + Modifier Effects¶
This color reference shows how Cempasúchil (Tagetes erecta) dye reacts to different pH modifiers. Each modifier changes the hue & brightness of the yellow–orange pigment. Use this card to attach your fabric samples or note your color results.
| Modifier | pH Reaction | Expected Color Tone | Suggested Fibers | Notes / Attach Fabric Sample |
|---|---|---|---|---|
| Neutral (no modifier) | pH ≈ 7 | Pure sunny yellow | Cotton + Wool | Base tone directly from dye bath |
| Vinegar (5%) | Acidic (pH ≈ 5) | Lighter, clearer yellow – slightly lemony | Cotton + Wool | Use ½–1 tsp vinegar in 500 mL water |
| Baking soda | Basic (pH ≈ 8) | Warmer, golden to orange tone | Cotton only | Add a pinch (≈ 0.3 g) per 500 mL water |
| Iron water (iron acetate) | Slightly acidic + metallic | Muted olive-gold or greenish yellow | Cotton + Wool | Test with 1–2 drops; darkens quickly |
| Lemon juice | Acidic (pH ≈ 5) | Paler, fresh yellow-pinkish hue | Cotton + Wool | Adds brightness; softer than vinegar |
FINAL RESULT¶
