Dyeing fabrics with indigo is an artisanal process that has been passed on from generation to generation in Thailand.
It typically involves the harvesting of indigo plants that are grown in local gardens. The plants are fermented overnight with water, after which ash, sugar, dried tamarind fruit and red lime (a mixture of lime and spices that is also used in Thai food) are added. The indigo solution needs to be constantly monitored and fed to stay alive and active.
ingredients used for indigo dying
It is a difficult process to master as it is dependent on many variables for the outcome such as temperature, humidity, water quality and so on.
the indigo solution
The end result color depends on how many times the fabrics are dipped in the solution, with the darker shades of blue requiring 20 times or more.
dark colors require frequent dipping
Unlike other methods of dying, indigo does not require a mordant, which is otherwise need to bond the color to the fabric. The fabrics also do not need to be cooked, but they are washed after dyeing with a mild detergent like dish water soap.
Indigo dyed fabrics have a distinct odor, which can be smelled when you hold the fabric close to your nose. It is not an unpleasant smell but very distinctive, it reminds bit of earth and farms.