of plants, dyes, practices and processes





Potassium aluminum sulfate, or alum, is a mordant frequently used in natural dyeing processes. It is a chemical compound of acidic nature which helps open up the fibres and thereby allows dye molecules to better bind to textiles. Using alum as a mordant for natural dyes thereby enhances the light- and washfastness, and strengthens colour uptake for more vibrant and durable results.



Private balconies or outside space connected to apartments in the city on which people grow and care for (dye) plants.


Biochromes refer to biological pigments, more specifically coloring compounds present in natural matter. In order to make use of biochromes for dyeing or coloring other matter, these need to be extracted from organic or inorganic matter from the animal, bacterial, botanical, flowers.

botanical cycles

In Local Color, the botanical cycles are one of the value chains that is being explored in the context of the city of Amsterdam. A variety of textile related resources come from botanically grown materials, think of indigo or woad leaves for traditionally dyeing blue in jeans, flax stems for crafting linen fibers, and many more.
This cycle is dictated by natural patterns, non-alterable or influenceable by human behaviour needs – such as the fast paced fashion requirements. It mostly require us to slow down: to re-sync with natural patterns and rethink our systemic value-chains to include a multiplicity of production patterns.

botanical garden

A collection of plants which are cultivated and displayed in organised garden lots, usually open to the public. The plants are documented and kept for conservation and education purposes, as well as presented in beautiful displays for visitors to view both outside and in green houses. Curated as a sort of living museum, botanical gardens often have plants categorised by origin, type and use.


chocolate cosmos

citizen plant caretaker

Individual person who joins the Local Color project to discover and learn about plants and natural dyes. This includes the Local Color community members who are growing their own Japanese indigo at home and who are joining the dye workshops.

cold stratification

Cold stratification is the process of subjecting seeds to both cold and moist conditions. Seeds of many trees, shrubs and perennials require these conditions before germination will ensue. Cold stratification simulates the natural process by subjects seed to a cool (ideally +1° to +3°C [34 to 37 degrees Fahrenheit]) moist environment for a period one to three months.

community garden

A site-specific organisation that is run by the local community on a volunteer-basis, collectively taking care of a garden area in their neighbourhood. Geographers typically define community gardens as open spaces where the cultivation of plants is taking place on a small scale by neighbourhood residents, conceptualised as a symbiotic practice occurring collaboratively between humans, nature and the urban environment. 
Community gardens form a social space where people can meet, further sustainable practices of growing their own (vegetable, herb, fruit or dye) plants and create a connection with nature in the urban landscape.


cosmos bipinnatus


dye garden

A green space where dye plants are cultivated with the intention of harvesting the plants for coloring or dyeing purposes. They are also excellent areas for bees and insects to thrive. Dye gardens serve both as a sustainable source of pigments for fibre and textile dyeing as well as an educational space to visualise and learn about plant dyes. Local Color is growing a first dye garden at Marineterrein where a range of plants such as madder, Japanese indigo, coreopsis, black hollyhock, cosmos and weld are making their way through the soil, growing for colourful harvests.


direct / substantive dyes

Types of botanical dyes which do not require mordant as pre-treatment on the fibers, in order to fasten the biochromes (coloring compound of a botanical dye) to the fibers. 


enabling city

By looking into the potential of urban space – the uses of the green spots of the city as well as the human networks it encompasses – Local Color researches the conditions of the ‘enabling city’ as a place that on one side facilitates the growth of local biochromes that can be used for closed-loop, local production on the small-city scale; and on the other creates a space that fosters learning and change.


Local Color stakeholder who is specialised in a specific area such as growing and dyeing, as well as policy makers within the fields of urban planning. 



fiber / fabric / yarn

Different forms of dyeable material, ranging from loose and disconnected fibers, to aligned and spun fibers (yarn), to woven knitted yarns (fabric) or connected fibers into a cloth (non-woven fabric)



green urban space

Do the bricks, stones, weeds and concrete of the urban environment shape the social and cultural fabric of the city? The relevance of green areas in studying urban spaces is shaped through the considerable interwovenness of the built environment and the social and cultural understandings which are embedded in it. The tangible elements that constitute urban environments become the playing field for the urban experience and in essence influence how people interact with their surroundings and shape the dynamics and flows of the city. 
One aspect of this urban materiality are green spaces which are particularly significant to the increasing focus on sustainability in urban planning. Spaces with nature; plants, community gardens, parks, wild weeds and trees frame the city and give citizens opportunity to interact with the materiality of the city in new ways, such as by growing dye plants in-between the bricks and asphalt. In addition to cultivating sustainable production patterns, this can also give citizens a sense of belonging and agency in rapidly-changing cityscapes.



Green areas in urban space which are not currently claimed or officially used by anyone. These transitional spaces can be found around urban landscapes where plants grow naturally or where the area has the potential of being used for local small-scale gardening.
In-between-greens can be imagined as soil or plants on a vacant lot, between trees, buildings, in unused urban spaces or on the side of the road. The Local Color project has mapped colorful in-between-greens in Amsterdam here.

invasive plant

As strange as it may sound – it’s a term coined to identify a plant that isn’t yet regarded as local – because it is not native to start with, and is disrupting the existing ecosystem at this moment in time. Invasive plants thrive of resources or land that is usually inhabited by other species, therefore invading their “space”.




japanese indigo

persicaria tinctoria
A plant traditionally used for dyeing, since the leaves contain pigments which extracts the blue colour indigo. Japanese Indigo is native to Asia and initially came to Europe as a dye source. This small plant lives for one year, enjoys a mix of sunshine and rain and is generally quite easy to grow. If kept happy, it will grow large and bushy, up to 60 cm tall – thereby producing plenty of leaves for natural dye. Japanese indigo is a social plant and grows long networks of roots, interlocking with neighbours in the soil. Looking at this lush green plant, its colourful secret is hidden within the leaves. The strong blue dye colour, significant to the Japanese Indigo, only appears when the leaves are crushed and the indigo comes in contact with oxygen. Read more about this exciting plant here.



stakeholder A place you can access that has technical equipment where you can conduct research and experiment with natural dyes, dyeing equipment, textile equipment or general printing equipment such as screen printing.

local color artist

A local stakeholder who works with natural dyes and creates textile objects or artworks out of naturally dyed materials.




double meaning The cartographic visualisation of geographical and spatial data, such as landscapes, routes, oceans and navigation characteristics. Mapping also refers to ways of laying out information and networks, connecting dots and people, processes and practices. Local Color is actively mapping stakeholders, spaces, historical dye practices, processes, gardens and plants, both visualising natural dye potential in the city and connecting people, plants and places.



Mordant is a substance that ties the dye to the fabric and ensures light-fastness and can enhance the dye molecules for more vibrant and long-lasting colors on fibers or textiles. There are many different types of mordants for different purposes and each have a different effect on the final color outcome. 
Historically, it is believed that Egyptians and Mesopotamians were the first to use mordant dyes and the practice of mordanting can be traced back thousands of years. Many things can mordants, such as metals and salts. There are also organic mordants that split into two parts: plant-derived and animal-derived mordants. It is not always necessary to mordant but most animal and plant resources seem to need mordanting when dyeing. 
The most commonly used mordants are alum, iron, copper and tin. Mordants can be used either as pre-mordanting before dyeing, or as a modifier after dyeing – these different methods make it possible to extract different colors.




As an essential nutrient for plant growth, adequate nitrogen levels of soil are crucial to the growth and development of plants. Different plants have varying needs of nitrogen levels, depending on the composition of the soil they are used to. For instance, Japanese Indigo likes higher amounts of nitrogen and thus grows well in Dutch soil which is known to have relatively high levels of it. Meanwhile, too much nitrogen adds to nutrient imbalance which has negative effects on a plant’s growth and health. Many fertilisers in agriculture are nitrogen-based and excessive use can lead to environmental issues such as soil degradation. As always, dosage makes the poison. 


organization / company

A formally established place with employees. As a Local Color stakeholder, they are working with an activity relevant to the creation of circular natural dyeing and textile production in Amsterdam.



Public green space within an urban area designated for recreational use. Parks typically have different plants – flowers, trees, bushes – growing in different areas. In the Local Color taxonomy, we recognise the urban parks as monitored green spots, thus cultivated, whereas forest areas which are larger and unmonitored are categorised as wild spots.

plant blindness

Term coined to represent a human behaviour of overlooking plants use and understanding, by botanists James H. Wandersee and Elisabeth E. Schussler



The act of spreading, communicating, or reproducing beliefs, ideas and information. In the context of gardening, propagation (plant propagation) means creating new plants from existing ones.
An example of propagation could be the spreading of the idea and inspiration to grow and propagate plants for natural dyes in the city where people may not expect botanical dyeing to take place – thereby, propagating plants becomes an act of propagating the knowledge of their dyeing potential.



At the end of the 16th century the Rasphuis, located on Heiligeweg in central Amsterdam, was a prison, or ‘tuchthuis’, for male prisoners in the city. During that time, prisoners were forced to grate (rasp) Brazilwood which was then used as red pigment for textile dye. For a long time this prison in Amsterdam had a monopoly on Brazilwood and citizens could pay to visit and watch the incarcerated at work. However, the rehabilitation efforts soon turned into the exploitation of inmates for cheap labour and the prison was closed in 1815. 


saint john's wort

hypericum perforatum


serratula tinctoria


‘Symbolic of latent, non-manifest forces, or of the mysterious potentialities the presence of which, sometimes unsuspected, is the justification for hope.’
 A Dictionary of Symbols by J.E. Cirlot

In the plant world, a seed refers to a fertilised ovule containing a plant embryo, thus forming an essential part of the plant cycle. Seeds spread and disperse in numerous ways, such as through birds and the wind carrying seeds from the plant to new places. As seeds turn into seedlings in the soil, they embody the potential of growing plants, thereby turning seeds into colour.



While the Rasphuis had male prisoners grating Brazilwood, female prisoners were spinning and sewing in the Spinhuis only a few hundred metres away. Active in the 17th and 18th century, the idea was that teaching the prisoners how to spin would keep them from engaging in what was considered criminal behaviour. Many of the women were incarcerated due to drunkenness or prostitution and were kept in a vicious cycle despite learning this task, as spinning was one of the lowest paid jobs at the time. Today the Spinhuis, located on Spinhuissteeg, belongs to the University of Amsterdam. 


Stratification is a process of treating seeds to simulate natural conditions that the seeds must experience before germination can occur. Many seed species have an embryonic dormancy phase and generally will not sprout until this dormancy is broken.

stressed plant

Cities tend to be busy, loud, unpredictable, smelly, polluted and fast. Like people tend to in dense cities, plants also get stressed, for instance when they lack water or sunlight. Luckily, plants have dramatic tendencies and like to show clearly when they are in a stressful environment. Their leaves droop, they might turn red around the edges of the leaves and stem, and produce fewer leaves. Japanese indigo even tends to flower early as a sign of stress, and the leaves turn upward as if trying to reach the sun with their tips.


temporary (green) space

Transient or ephemeral areas that are temporarily transformed into an area with plants and greens. Urban areas are known to be in constant change, and the usage of a place is often temporary – be it construction sites, old buildings, or forgotten lots – the city provides a wide variety of opportunities for growing and greening in spaces which were not initially intended for plant cultivation. 
In a city like Amsterdam where space is scarce, the temporary nature of urban spaces can be viewed as an opportunity for circular, local-production in the city. For instance, the Local Color dye garden on Marineterrein was a car parking lot before it was turned into a green space. 
Working within the temporality of these spaces creates interesting dynamics of urban planning, seasonal plant cycles and social movement in the city.

textile cycle

This textile cycle includes 16 stages of circulair textile production from yarn spinning to product use to recycling. The textile wheel was developed in the European Union Horizon 2020 project called Reflow by the Amsterdam Pilot consisting of the Amsterdam Municipality, Bma Techne, Pakhuis de Zwijger and Waag’s TextileLab. The cirulair textile wheel envisions how to move from a lineair to a circular textile flow. The booklet that describes all stages in detail can be downloaded via this link.

textilelab model


Derived from the Latin tingere, meaning ‘to dye’ or ‘to paint’, this epithet is used for naming and classifying plants in order to indicate that the plant has historically been used as dye or colouring material. The plant species usually produce special pigments which can be extracted for natural dye – examples of this are serratula tinctoria (sawwort), rubia tinctoria (madder) and persicaria tinctoria (Japanese indigo). However, it is important to note that not all plants that can be used for dyes have this classification, as a single species often carries a multitude of potential uses and dyeing may be just one of them.

traces of textile history

The textile industry has been present widely throughout Amsterdam’s history, leaving traces scattered around the central streets and canals. For instance, the Verversstraat (dyer’s street) between Nieuwmarkt and Waterlooplein brings us back to the Middle Ages when the textile industry played a big role in Dutch trade and manufacturing. Similarly, Raamgracht refers to the wooden frames in which dyed cloth samples were stretched and Staalstraat brings us back to the staalmeesters (fabric sample officials) who were assessing the quality of the textile samples. In an interview for Local Color, local artist Heleen van Deur talks about the rich textile history that once blossomed in the city. You can read the interview here.
Furthermore, Local Color organised a meet-up and textile-historic colorful walking tour through the Nieuwmarkt area which you can trace embark on by following this map.


urban farm

A garden – usually with herbs, fruit and vegetables – professionally cultivated and run by an organisation where people can purchase fruits and greens as well as harvest in the gardens themselves. 



value chains

A system that uncovers and revalues existing resources that the city is rich through the exchange and repurpose of material streams while fostering sustainable practises among local stakeholders and communities. Local Color envisions a collaborative system defined and connected through shared values that is respectfully adaptive to one and another. You can read more about value chains here.




isatis tinctoria