BY Michele Wipplinger | August 18, 2011
The beginning of Blue
Indigo is a leguminous shrub that is cultivated throughout the world, from the tropics to temperate climates. It is one of the world’s oldest dyestuffs. It is mentioned in Indian manuscripts from the 4th century BC, and by Marco Polo in his writings as he traveled through Central Asia and beyond. Indigo blue is a dye to behold; a dye that requires an intuitive sense of alchemy and the visual perception to identify the variety of plant species that by nature yield a wide variety of blues. It is the color of the sky, the sea, the Hindu god Vishnu and was the favorite color of Matisse during his early years. When a baby is swaddled in indigo dyed cloth they can rest peacefully. Indigo is a natural insect repellent deterring any nasty bites.
Historically indigo dyeing is practiced according to family traditions based on cultural knowledge that has been passed down through generations. Each dyer, each plant species and the variety of processes that have been used traditionally result in rich color variances: shiny blackened-blue gleaming cloth from an egg-white surface application (SW China), Levi blues from North America, warm green-blues from fresh leaf dyeing (SE Asia) and an aubergine casted indigo blue when the bark of a Morinda (a madder variety) is added to the indigo bath (West Africa). The natural indigo fermentation process is culturally specific and the dyeing methods just as idiosyncratic. Artisans continue to this day growing and composting indigo leaves using the resultant plant extract to create a world of blue.
Indigo cultivation and dyeing is still being practiced in countries all over the world including: Bangladesh, China, El Salvador, Guatemala, India, Indonesia, Iran, Japan, Korea, Mexico, North Africa, Pakistan, SE Asia, The EEU, Turkey, Uzbekistan, West Africa and a select group of countries in South America (Brazil, Bolivia, Chile, Ecuador, Paraguay and Peru).
Regardless of the origin of indigo, when cloth or yarn is dipped into an indigo vat repeatedly over a period of days into months, it is imbued with a rich dark shade and often a toothy crisp hand. Indigo dyed cloth will range in color from a yellow-based blue (Indigofera tinctoria) to a red-based blue (Indigofera guatemalensis) and a blackened-blue when iron rich mud is mixed with the indigo.
Indigo Extraction Process the African Way
The primary indigo plant variety used throughout West Africa is Lonchocarpus cyanescens (often referred to as “Yoruba indigo” or “gara”). The following indigo dyeing description is based on the processes used by West African dyers from Burkina Faso, Gambia, Guinea, Mali, Nigeria and Senegal.
The best time for harvesting the leaves of the Lonchocarpus species is just before flowering when the plant contains the highest amount of indigotin. The leaves, flowers and stems of Lonchocarpus are collected during the rainy season and then macerated with a pestle in an over-sized wooden mortar until the leaves become a pulp. The plant mass is then formed into balls approximately 10-12 cm in diameter and dried in the sun over two or three days. The indigo balls are sold in the local markets of each region in West Africa or used by the artisans who make them. The local dyers may use up to fifty indigo balls in a single dye bath to achieve a medium dark blue and up to 150 indigo balls for a rich black-blue shade
The creation of a successful indigo bath from the pulverized indigo leaves requires the addition of an alkali which in West Africa derives from the addition of water that has been leached through wood ash from cooking fires. Any excess ash is gathered and formed into balls using water as the medium for holding the mass into a compacted ball or rock-like shape to be stored for future use.
Next the ash water is added to the crushed indigo balls and left to steep over three days in the hot sun. This solution is stirred occasionally throughout the steeping period. The stitched or tied cotton cloth is then added to this indigo bath, carefully submerged and moved regularly to ensure even dyeing over the next two to three days. The dyed cloth is then removed to either dry (without rinsing) or to be oxidized over 24 hours and dipped again in the indigo bath to achieve a blackened blue color. This indigo dyed cloth, regardless of depth of shade is never rinsed. The Dogan people of Mali use subtle small stitches to define their designs which after indigo dyeing appear as continuous fine lines, small geometric squares and irregular delicate dots.
Throughout West Africa starch resist (cassava paste) is applied to cotton cloth using a variety of hand painting methods with simple tools (i.e. twigs and sticks) to create delicate or bold lines on cotton cloth as another creative option when dyed in the indigo bath. The patterns that are achieved when using this method are rich in detail and often cover the cloth in flowing or repetitive motifs. Typically when the cloth is removed to oxidize the indigo on the cloth it will be refolded in another direction before the second dip creating subtle variations in the values of the indigo blue dyeing. The final indigo dyed cloth is allowed to oxidize over a twenty four hour period of time at minimum to develop the rich dark indigo color.
Although the use of synthetic indigo dominates in many parts of West Africa, the creation of macerated indigo balls persists in pockets of this region including San and Segou in Mali and among the Wolof of Senegal and the Yoruba of Western Nigeria. The practice of macerating indigo leaves and forming them into crude, juicy balls of blue is still being practiced, albeit in fewer and fewer places.
Throughout West Africa there is a renaissance in the use of local tannins and other plant dyes to create a broader range of colors to be used in combination with indigo. Plants such as Kola nuts (Koalanetida), African grape (Lannea mekokaba), African birch (Anogeissus leiocarpa), onion skins (Allium cepa), henna (Lawsonia inermis) and Camwood (Baphia nitida) are just a few of the other locally available plants in West Africa that provide rich background colors over which indigo and tannin-rich mud can be applied.