Red cabbage dye is my favorite natural blue dye for cotton fabric and cotton clothing! 😀 You can use red cabbage to dye cotton blue even without a mordant. Or you can make DIY iron mordant to make the color darker and to improve the wash fastness of red cabbage dyed fabric.

Related: How To Dye Cotton Blue With Red Cabbage (No Mordant)

Over the years, I made many dyeing experiments with red cabbage dye: Trying out different mordants and modifiers, cold dyeing and hot dyeing methods, different ph-levels during the dyeing process etc.

Below is a list of frequently asked questions of my readers about dyeing cotton fabric with red cabbage dye.

Related: How To Dye Cotton Fabric Black Naturally

By the way, besides as a fabric dye, you can also use red cabbage to dye food blue or to dye Easter eggs!

Related: How To Make Natural Blue Food Coloring With Red Cabbage

9 FAQs About Dyeing Cotton Blue With Red Cabbage

What Do I Need To Get Started With Red Cabbage Dye?

You’ll Need:

• red cabbage
• water
• pot
• spoon or wooden stick (to stir the natural dye and lift the fabric out of the dye)
• knife (to cut the red cabbage into strips)
• cotton fabric, cotton yarn or cotton clothing (for dyeing)

Because red cabbage dye is edible, you can use a pot that you also use for cooking food if you don’t use iron mordant. If you use iron mordant, then use a separate dyeing pot that you only use for dyeing.

Before dyeing with red cabbage, pre-wash the cotton fabric (or cotton clothing).

Related: How To Dye Cotton Blue With Red Cabbage (DIY Iron Mordant, Cold Method)

I Want To Try Red Cabbage Dye But I Don’t Want To Waste Food!

I also don’t like to waste food for natural dyeing and the good news is that you don’t have to waste food! You can use the limp outer leaves of the red cabbage that you’d throw away anyway for dyeing and use the rest of the red cabbage for eating. And you can also use red cabbage that is no longer suitable for eating: I recently used a head of red cabbage that was moldy on one side. I cut off the mold and used the rest to make a natural blue dye! It still produced a strong blue on cotton.

Can I Dye Cotton A Different Color Than Blue? I’ve Seen It On Other Blogs.

No, you can dye cotton only blue with red cabbage – that is if you wash and wear your naturally dyed piece of clothing like any other clothing! Only if you plan to never wash your red cabbage dyed fabric – e.g. an artwork – then you can modify the naturally dyed blue fabric: you can turn the naturally blue dyed cotton fabric pink with an acid – like vinegar or lemon juice – and you can turn it green and even yellow with a base – like baking soda or washing soda. However, your modified fabric will turn back to blue once you wash it again! 😉

Related: Red Cabbage Dye Samples

Why Can You Dye Cotton Blue With Red Cabbage?

Dyeing is a chemical process: While animal fibers like wool and silk are slightly acidic and will turn purple with red cabbage dye, plant fibers like cotton are slightly basic – like egg shells – and turn blue with red cabbage dye.

Related: 19 Ways How To Dye Easter Eggs Naturally

If Cotton Is Basic, Can I Get A Better Blue If My Red Cabbage Dye Is Basic Too?

After experimenting a lot with different ph-levels during dyeing with red cabbage, I found that red cabbage dyes best if the dye solution is slightly acidic (around 5) but not too acidic (3 or more acidic). And if the red cabbage dye solution is basic, then it won’t dye a washfast blue on cotton.

Related: Red Cabbage Dye & Washing Soda

How Can I Adjust The Ph For A Perfect Blue Dye?

While you’re extracting the dye from the red cabbage leaves, the dye solution can turn slightly basic or slightly acidic depending on the temperature, the bacteria that are present where you live and other factors. It’s a natural process and you can’t control it! 😉 Both has already happened to me: that the dyeing solution has become basic and acidic while I was extracting the dye! But if this happens you can easily adjust the ph back to around 5.

If the red cabbage dye solution is too basic make it more acidic with vinegar or lemon juice. If the red cabbage dye solution is too acidic make it more basic with baking soda. Add a little at a time, stir and wait for about a minute. Then add more if necessary.

I Don’t Have Ph Paper. How Can I Adjust The Ph?

If you don’t have ph test strips at home, you can still easily control the ph-level. Use a small piece of pre-washed white cotton fabric and dip it into your red cabbage dye solution. If it turns pink, your dye solution is too acidic. If it turns blue, green or yellow, then your dye solution is too basic. If your fabric turns purple (rather bluish purple than pinkish purple), then the ph of your red cabbage dye solution is right! 😀

Is Red Cabbage Dye Lightfast & Washfast?

Yes, red cabbage dye is lightfast and washfast. However, keep in mind that natural dyed fabric will fade over time. But even fabric dyed with synthetic dyes will fade over time! 😉 Red cabbage dyed fabric usually fades to gray blue, pale blue or gray.

How Should I Care For My Red Cabbage Dyed Fabric?

You can protect your natural dyed fabric by not washing it too hot, not using harsh laundry detergents or bleach, and drying it in the shade instead of in the sun. And if your natural dyed fabric fades over time, you can always re-dye it with natural red cabbage dye! 😀