Natural dyes: their history and how to make them
A comment on one of my hubs, that on the negative effects of the petroleum and of the petrochemical industry, has led me to write this article, to demonstrate that man could easily survive and have all that he wishes for, even without polluting the environment and destroying it...as in the old days!
Cultivation and use of dye plants was very common in Europe up to the end of the 19th century; pigments from leaves, fruits, seeds, wood and roots were used as dye stuffs for textiles and as a paint in art and craft. The discovery of synthetic dyes led to a breakdown of the natural dye market and, as a result, cultivation of dye plants came to a standstill.
Natural dyes, made from plants, animals and shells provide important alternatives to petrochemical-based dyes and, if harvesting is carefully managed, offer environmental and social benefits; in comparison with synthetic dyes, natural dyes have large variations in colour tone, because of the quality differences of different provenances of the dye plant. They obviously require longer, slower dyeing treatments to achieve good color, particularly for vegetable fibers, making the process more costly than dyeing with synthetics. The synthetics are cheap and easy to use, rapidly, in the past century, they supplanted the natural dyes for commercial dyeing. One of the reasons why chemical dyes are suitable for commercial purposes is that the cloth from every dye bath will be almost identical in colour; one of the pleasures of dyeing with herbs is that no two baths will ever give exactly the same results, there will always be an element of surprise, with variations according to the season, the weather, the maturity of the plant, its position in the sun or shade and the quality of the water used for dyeing.
Yet the higher cost, subtle color variation and greater demands on time means that natural dye technology has a particular cachet and quality that works well in specialist production. In fact, over the last few years synthetic dyes have been losing good reputation because of the risk of toxicity, negative influence on the environment and high allergic potential. Consequently, an increasing demand have naturally developed. Really, no chemical dye can achieve quite the depth and lustre of many plant dyes; the rich and subtle variations of tone and colour derived from plants may mellow and soften with time but never will lose their natural harmony.
History of the natural dyes
The use of colorants dates back thousands of years in all societies around the globe. Even before people began to spin yarn and weave cloth, they applied colored earth, plant saps and juices directly to their skin: this was the first type of cosmetics. Women in Mediterranean region applied alkanet as rouge and lipstick and used chamomile and henna to dye their hair. Indians in Soth America prepared a paste of annato seeds for painting their bodies. Applying dyes to fibers and fabrics is more complex than simply using plant to stain the skin, but throughout history, people have developed systems of dyeing.
Among the ancient peoples, the Egyptians of the Middle kingdom not only dyed textiles but also understood the use of mordants (metallic salts with an affinity for both fibers and dyestuffs that improved the colorfastness of certain dyes) as it is described by Pliny the Elder: "In Egypt they dye clothing in a remarkable way. The white material is treated not with colors, but with mineral compounds which absorb the colors. This done, the materials appear unchanged, but when immersed in a cauldron of boiling dye and immediately removed, they are colored. It is remarkable that though the dye in the cauldron is of one color only, the materials when taken out are of various colors, according to the quality of the mineral compounds applied, and it cannot afterwards be washed out."
The Phoenician dye industry, begun in 15th century BC, was renowned for its Tyrian purple, or royal purple obtained from a species of shellfish processed in the city of Tyre, which actually produced a range of colors from red to blue, icluding violet.The Greek physician Dioscorides and the Roman naturalist Pliny the Elder, both writing in the first century, described sources of dyes and dyeing techniques known in those days, they mentioned several of the dye plants, including indigo and woad for blue, alkanet and madder for red, weld and saffron for yellow, and oak bark and walnut hulls for golds and browns.
India, the country whose dyeing practices have exercised the greatest influence on European dyers from the 16th century, appears to have had a dye industry long before its transactions were recorded in writing, perhaps extending to the period of the Indus Valley civilization ca 2500 BC. Dyers in India and southeast Asia not only mastered the art of producing bright colors on cotton (no mean feat), but also developed techniques for printing colors on woven fabric and making designs with resisting dyeing. Marco Polo described in detail its indigo manufacture during the 13th century AD, about three hundred years before the Portuguese introduced it to Europe.
Our major dyeplants, along with our staple foodstuffs and a vast dispensary of medicinal plants, were all recognized thousands of years ago. Most modern people, who shop for food and drugs in supermarkets and buy their clothes already colored, are relatively unaware of the plants in their neighborhoods; if they think about them at all, they feel bewildered by all the different kinds of grasses, herbs, bushes and trees, and can't imagine how anyone could ever tell one from another. Earlier generations of people had a deeper love for the environment and explored it very thoroughly. So they learned which plants were nourishing and which were poisonous, which contained fibers, which provided dyes, which were narcotic. Sooner or later, they found all the good stuff: for example, the blue pigment indigo is invisibly present in several completely different kinds of plants, but ancient dyers found these varied sources and learned to extract indigo and use it as a dye.
Colors often play roles more important than mere decoration or ornament: they serve as cultural symbols. Different colours may be associated with cosmic and religious forces, with status and class, with illness and health. Some beliefs about color persist: brides wear with and widows black, baby boys wear blue and baby girls wear pink, Halloween colors are orange and black etc. In societies more governed by tradition, rules for using specific colors were much more strict; choice dyes from rare sources were reserved for the garments of the kings or priests; some colors of clothing were believed to protect the wearer from earthly pests and diseases or from supernatural forces: many societies have attached strong significance to colors.
Plants and colours
The colour that a dyeplant produces depends on the season in which the plant is picked and this because many factors influence the outcome of any given harvest of plant material, factors which include: soil fertility, moisture supply, temperature and day length. The most intense colours are given by plants in full bloom where the flowering parts are used for dyeing. Early spring is the best time for collecting bark from trees; there is no need to break off the entire branches or to cause unnecessary harm to the tree: simply, in springtime, when the trees are being pruned, the cuttings can be picked up. Nuts should be gathered from the ground as soon as possible after they have fallen. So, different parts of the same plant will contain different amounts of pigments, and the pigment content varies at different stages in the plant's life cycle. As examples: madder plants grown in rich, slightly alkaline soil give more red dye; woas leaves harvested when the plant is in bloom have lost most of their potential to give blue etc.
If all else fails, dried plants can be purchased at some stores that sell wool for spinning and dyeing. However, plants give their best dye if they are used immediately after being picked: the colour will change if a plant is dried and then used at a later date; moreover, some plants cannot be stored at all (such as dandelions, horsetail, goldenrod, carrot tops etc.)
One easy way of determining if a plant will dye wool is to rub parts of it between your fingers: if a coloured poweder comes off, the plant probably will produce a good dye.
The brown dyes can be obtained from the bark of apple, birch, hemlock, hickory and maple tree; yellow from a wide variety of sources such as arsemart, white ash bark, barberry bark, sassafras, lichens, camomile flowers, and coffee beans; reds from madder, cochineal, Brazilwood and alkanet; blues from woad, chemic, orchil and cudbear, as well as from the popular indigo; and blacks most commonly made from logwood and soot. Also there is the possibility of combining any of these by top-dyeing.
Flowers, leaves, stems and bark, seeds and fruits, and wood assume their characteristic colors because they contain naturally colored compounds called pigments; biochemists have identified thousands of different pigments produced by plants. Why are there so many? It's known that some pigments play important roles, but the biological significance of most pigments is still a mystery. Not all pigments serve as dyes. Some pigments will not dissolve in water, some dissolve well and make a brightly colored solution but have no affinity for fibers, some others, after dyeing, promptly fade away and some lose their color when they react with oxygen in the air, especially in the presence of sunlight. So, although there are lots of colored substances in plants, there are only two or three dozen pigments of lasting value to weavers.
How to make the natural dyes for clothes
The first step in dyeing, after gathering the plant material, is to get the color out of the plants and into a pan of water. Some plants require special procedures, but in general, it's a simple matter that can be easily reassumed so:
1) Shed fresh, soft plant parts, such as flowers and leaves, into a pan, cover with water, and simmer for half hour to an hour, until the water is colored and the tissues look bleached out. If the flowers or leaves have been dried, soak for several hours or overnight and then simmer in the same water.
2) Press down on juicy fruits or berries to break the skins, then cover with water and add a little vinegar. Soak a few days at room temeprature for best results.
3) Chop or grind hard material, such as roots, bark or nut hulls, into chips: the smaller the chips, the better the dye flows (a hand-cranked flour mill or meat grinder works well). After grinding, soak the chips or meal for a few days, then heat and simmer for an hour or more.
After, I usually prefer to make a dyebath and filter it through a mesh strainer, then add the fibers to the filtered liquid. Remember that the dyebath concentration can be weak or strong, depending on different factors. dry dyestuff are more concentrated than fresh material. But knowing exactly how much dyestuff to use is partly a matter of following recipes and partly a matter of experience. If the first batch of fibers dyes to a good dark color, you can enter, second, third and successive lots of fibers and get progressively paler shades, this gives a lovely sequence of coordinated colors ranging from vivid to pastel...very similar to creating colors for painting, isn't?
After, one must control the pH of the dyebath because it is very important, as it affects the colors that will be produced. Some plants pigments dissolve much better in acidic than basic solutions, and vice versa. Some pigments change even color in different solutions!
Traditionally, dyers have added various substances to dyebath solutions to obtain the best results with particular plants- all are natural additives that cause not any harm to the environment, contrary to the household chemicals. As alkaline additives, can be used: stale urine and dung, wood and plant ashes, lye and chalk; for acid additives, can be used: vinegar, sour wine, fermented fruit juices, sour milk, rhubarb, sorrel leaves and tree leaves and bark containing tannins.
Most plant dyes give better results if used in combination with a mordant; early dyers realized that a mordant enables the dye to get a better bite on the fibres, because mordants increase the uptake of dye on the fibers, giving brighter, deeper colors, they increase the dye's fastness to light and washing and they also can increase the range of colors which can be obtained from a single dye plant. Here a brief list of the most popular mordants:
-Aluminium: a few plants are sources of aluminium and can be used as natural mordants; these include club mosses, leaves of the sweetleaf tree and its tropical relatives, and tea leaves.
-Lichens: they can be used as a pre-mordant, and they provide pale ground colors on which could be added after others colors to get a soft pastel color. (By the way, they produce also a wonderful aroma).
-Salt: it is a bath additive and improve the fastness, but it has to be firstly dissolved in boiling water.
-Vinegar: it could be used both as a bath additive or as pre or post- dye treatment; if used as a bath additive, it will lowers the pH, and if used fro pre and post dye treatment, it shifts colors (a color like magenta, as example, will shift to deep rose). Plus, weak acetic acid like vinegar will help keep your wool from degrading.
-Chalk: it is very important for the production of a good bright yellow, or wonderful red with madder; it improves generally the color. It is one of the few that doesn't need to be boiled first, it has to be added to bath at the end of the heating.
Other natural mordants iclude: birch, oak (especially black oak soaked in standing water for two years), currants and gooseberries (acidic mordants that can help make colors more permanent); hardwood or cedar bark ashes, female dock root (to achieve deeper colors).