How to Dye Silk with Natural Dyes

Can you dye silk with natural dyes? Yes! Silk is a protein fiber, and protein fibers take natural dyes very well, often better than cotton and linen. All fibers should be scoured before dyeing for the best results. Think of your textile as a painter's canvas: when it is well prepared, your colors look better. That is why we recommend a mordant for silk too, so the colors last. Only with indigo or woad, or with tannin-rich dyes, can you skip the mordant.

Know your silk

Different silk fabrics take natural dyes differently: smooth habotai, crepe, chiffon, raw silk and peace (ahimsa) silk all give slightly different results. If you are not sure what kind of silk you have, find out before you dye.

What you need

• Undyed silk that is ready to dye
• A natural dye extract or raw natural dye
• Alum mordant (potassium aluminum sulfate)
• Optional: cream of tartar
• A scale and measuring spoons
• A stainless steel pot (10 liters or more) and a large bowl
• A stainless steel spoon (silk can catch on the rough edge of a wooden spoon)
• Rubber gloves

Step 1: Mordant the silk

1. Weigh the silk dry.
2. Make sure the silk is completely clean: wash it gently with a pH-neutral soap.
3. Soak the silk in warm water with a drop of mild washing liquid for several hours or overnight.
4. Weigh the alum: 10–15% of the dry weight of the silk (10–15 g for 100 g of silk). You can add 5% cream of tartar for brighter colors.
5. Dissolve the alum in about 1 liter of boiling water.
6. Fill the pot three-quarters full with hot tap water and stir in the dissolved alum.
7. Add the wet silk and work it gently into the mordant. Wear gloves.
8. Leave the silk in the pot for 24 hours without heat, stirring gently now and then. This cold method protects silk's natural shine.
9. Take the silk out. Rinse it gently and dye it, or dry it and dye later.

For a heated method, see how to mordant wool and silk.

Step 2: Dye the silk

1. If the mordanted silk has dried, soak it in warm water for at least two hours, ideally 8–10 hours, so it takes the dye evenly.
2. Weigh the dye. Use the suggested amounts on the product page; for extracts this is usually 2–10% WOF. Ask us if you are unsure.
3. Mix the extract into a paste with a little hot water. Fill the pot with hot water and stir in the paste.
4. Add the wet silk. Keep the bath warm, no hotter than about 80 °C (175 °F), for an hour, or simply leave it in the hot bath overnight. Stir now and then with a stainless steel spoon.
5. Rinse the silk in warm water, wash gently with pH-neutral soap and dry it in the shade.

Tips for dyeing silk

• Avoid high heat and sudden temperature changes, which can dull silk's shine.
• Do not wring or twist silk; gently squeeze out the water.
• Silk is ideal for bundle dyeing and eco printing.
• For pinks without a mordant, try safflower.

Related: Natural dyes: complete guide · How to dye with natural extracts · Shop natural dyes