why scour fabric when using natural dyes? Plus my recipe to do it.

Why Scour Fabric When Using Natural Dyes?

Why Scour Fabric When Using Natural Dyes?

So, in everything you read and every class you take, you’re directed to scour your fabric before you dye it. But to be honest, I often skipped this step until very recently. Because the dyeing process I use involves thrifted fabric, vinegar baths and then days with rusted objects, I felt I must have broken down all the impurities there could be. Right? Nope! After doing some tests, I can say that no matter what process you use, scouring your fabric will impact the colour. 

Interested in dyeing fabric with rust and natural dyes? Check out my kit! Everything you need is included (except rusted object) AND I have scoured the fabric for you. 🤩

Here are a few more reasons to follow this step in your dyeing journey:

1. Remove Impurities:

   Natural fibres, such as cotton, linen, and wool, often contain impurities like waxes, oils, dust, and other contaminants from the manufacturing and processing stages. Scouring helps to eliminate these impurities, ensuring a clean and receptive fabric surface for the dye.


2. Enhance Dye Absorption:

   Scouring opens up the fibres and removes the natural oils and substances that can hinder dye penetration. Cleaning the fabric thoroughly creates a more porous and absorbent surface, allowing the natural dyes to penetrate the fibres more effectively and produce vibrant, long-lasting colours.


3. Ensure Even Dyeing:

   Uneven scouring or incomplete removal of impurities can result in uneven dyeing. Certain areas of the fabric may absorb more dye than others, leading to patchy or mottled colours. Proper scouring helps to achieve a uniform and consistent coloration across the entire fabric.


4. Improve Colour Fastness:

   Scouring contributes to better colour fastness by eliminating substances that may interfere with the bonding of the dye molecules to the fibres. This helps create a more permanent and colorfast result, reducing the likelihood of fading or bleeding over time.


5. Minimise Environmental Impact:

   Scouring can involve the use of detergents or natural scouring agents. Thorough scouring at the beginning of the dyeing process reduces the need for excessive dye or mordanting agents, contributing to a more environmentally friendly dyeing process.


6. Optimise Dyeing Efficiency:

   Scouring prepares the fabric for the dyeing process, making it more efficient. Properly scoured fabric requires less dye and shorter dyeing times to achieve the desired colour intensity, thus saving resources and energy.


7. Promote Consistency Across Batches:

   In industrial settings or when dyeing large quantities of fabric, scouring helps maintain consistency in colour results across different batches. Consistent scouring practices ensure that each batch of fabric has a similar starting point for the dyeing process.


Scour water. before and after


Here is my recipe for scouring fabric:

For Treating 1 Pound of Cellulose Fabric (Equivalent to approximately 2 average-sized t-shirts): 


  • 1 teaspoon of pH Neutral soap (Dawn, Synthrapo, Mrs. Meyer’s, etc.)
  • 5 teaspoons of Soda Ash 4 litres of water (sufficient for the fabric to move freely)


  1. Begin by filling a dye pot with lukewarm water and place it on high heat. 
  2. Pre-wet the fabric with tap water. 
  3. Add soap and soda ash to the water in the pot. 
  4. Heat the water until it reaches an approximate temperature of 180°F (82°C) just before boiling.
  5. Add fabric into the pot, and ensure thorough mixing of the fabric with the solution.
  6. Allow the fabric to sit in the pot over high heat for 2 hours, stirring occasionally to maintain consistency.
  7. With caution and using appropriate tools such as a spoon or tongs, remove the fabric from the hot water and transfer it to a bowl or directly into the sink. (Handling the fabric in this step requires utmost care due to the high temperature). 
  8. Immediately rinse the treated fabric thoroughly with fresh water to remove any remaining residues. 
  9. Finally, hang the fabric to dry. 

**Note: For silk fabric, reducing the sitting time in the solution to 1 hour is recommended to avoid damaging the fibres.

 If you want to learn more about natural dyeing with rust check out my ebook

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