Natural Dye — An Introduction

What It Is

Natural dyeing encompasses the extraction of colourants from natural sources and their application to textile fibres through a process involving mordants — mineral salts that bond the dye to the fibre. The three core variables are: the dye source (plant, insect, mineral), the fibre (protein-based or cellulose-based), and the mordant (which determines the final colour and wash-fastness).

Fibre Types

Natural dyes behave very differently depending on the fibre:

• Protein fibres (wool, silk): Easiest to dye — their amino acid structure bonds well with most mordants. pH must stay between 8–9; above 11 will damage or dissolve the fibre. Most mordant processes work well without additional protein treatment.
• Cellulose fibres (cotton, linen): More difficult — their structure does not bond as readily with dye. Mercerized cotton is easier than unmercerized. Linen is the most difficult. Cellulose fibres often require an additional mordant step — soy milk, oak gall, or aluminium acetate — to improve dye uptake.
• Note: Most plants yield yellow as the base tone. Getting red, blue, or deep colour often requires specific dye sources (cochineal, indigo, tannin-rich barks) combined with specific mordants.

Core Process

Scouring (정련): Clean the fibre before dyeing. For cotton: 1% soap + 1% soda ash in hot water, 30–45 min. For wool and silk: warm water (40–50°C), 30–40 min — avoid agitation to prevent felting.

Mordanting (매염): Apply a mineral salt that bonds with both the fibre and the dye molecule, locking in colour. The choice of mordant changes the colour significantly. See: Mordanting.

Dyeing: Extract colour from the plant source in water, then immerse the mordanted fibre. General ratio: 1 litre of water to 50g of fibre. Bring to boil, reduce to mid heat for 30 min, rest for 12 hours for deep colour. Filter dye bath if needed.

Washing and drying: Rinse in water of similar temperature to prevent felting (wool/silk). Air dry away from direct sunlight.

Key Principles

• Indigo before all other dyes: Indigo is alkaline; most natural dyes are acidic. Dye with indigo first to avoid contaminating the vat with acid residue from other dyes.
• Distilled vs tap water: Water quality affects colour significantly. Tap water with high mineral content can shift colour. Distilled water gives cleaner, more predictable results.
• Fresh vs dried botanicals: Fresh plant material generally gives stronger colour. Some dried materials work equally well (dried marigold, dried cochineal). Barks require long boiling to release tannins; petals should not be boiled — use maceration (cold soak) instead.
• Lightfastness: Yellow dyes from most plants fade fastest. Indigo (alkaline) and cochineal are among the most lightfast natural dyes. pH-sensitive dyes (red cabbage, beetroot) fade quickly with exposure to light.

Jay's Studio Note

Natural dye practice was first learned in Oaxaca, Mexico — where the local dye tradition (cochineal on wool, indigo on cotton and silk) is one of the most sophisticated and living traditions in the world. The September indigo harvest in Oaxaca is a specific seasonal event, and the relationship between altitude, water source, and dye result is something that no recipe fully captures. Later work in CDMX and Buenos Aires continued the practice. The most surprising discovery: the same dye, the same mordant, different water — completely different colour.

Related Entries

Indigo Vat — 3-2-1 fructose vat recipe · Cochineal — insect dye, 30% concentration · Mordanting — alum, tannin, soy, soda ash · Botanical Dye Plants — marigold, weld, palo de brasil, walnut · pH & Colour

Maceration — Cold Extraction for Delicate Pigments

Maceration is the process of extracting colour from plant material in cold or room-temperature liquid, rather than through heat. It is essential for plant materials where boiling would destroy the pigment — particularly delicate petals and flowers.

Process: Place plant material in water or diluted alcohol. Leave for 12–48 hours at room temperature, or longer in the refrigerator. Strain and use the coloured liquid as a dye bath, or concentrate by gentle low-heat evaporation (never boiling).

Use maceration for: Rose petals, calendula, lavender, chamomile, hibiscus, and other delicate flowers. Most plants with intense fresh colour but fragile pigments.

Use boiling for: Barks, roots, dried berries, nutshells, hardwoods. These require heat to release tannins and dye compounds.

Rule of thumb from field practice: if the plant is tender and fragrant, macerate; if it is tough and woody, boil.

Basic Dye Ratios (field notes)

From Jay Lee's Oaxaca natural dye practice:

• General dye ratio: 1 litre of water to 50g of dry fibre (WOF = weight of fibre basis)
• Basic process: Mordant fibre (alum → vinegar → soda ash overnight, agitating to mix; wash with hot water) → start dyeing in pot bringing to boil, lower to mid heat for 30 min, rest for 12 hours → filter
• Palo de Brasil: 382g of wood per 2.5 litres of water
• Walnut: 200g seed material per 2L water, 20 min boil; 20g alum on hot filtered water after stretching; 8g alum per litre