Natural Indigo

Natural indigo is the classic plant blue, extracted from Indigofera tinctoria leaves. Unlike most natural dyes, indigo needs no mordant: it is reduced in an alkaline vat, the fiber is dipped, and the color develops as it oxidizes in the air. Our natural indigo extract and fructose powder are everything you need, together with soda ash or lime, for a fruit-sugar indigo vat.

How the fructose indigo vat works

In a fructose vat, sugar reduces the indigo and an alkali raises the pH. The vat is gentle, non-toxic and can be kept going for months with small additions. Dip your scoured, wet fiber slowly, let it oxidize from green to blue, and repeat for deeper shades.

Shades and combinations

Short dips give pale sky blue; many dips build navy. Overdye indigo with weld or buckthorn for greens, or with madder for purples. Indigo works on cotton, linen, wool and silk.

Frequently asked questions

Do I need a mordant for indigo?

No. Indigo is a vat dye and bonds by oxidation, so no mordant is needed.

How much indigo do I need?

A small amount goes a long way: a few grams per liter of vat is a typical starting point, and the vat can dye many items.

Is natural indigo the same as synthetic indigo?

The blue molecule is the same, but natural indigo is made from plants and contains other plant compounds that give a softer, more varied blue.

Explore more: Natural Blue Dyes · Dye Assists & Modifiers

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