ORGANIC OAK BARK DYE

Oak Bark Natural Dye

Quercus spp. · Poland · Dried and Cut

Oak bark is a traditional, tannin-rich dye material used to create warm golden beige, tan and earthy brown shades.

Its naturally occurring tannins give it an affinity with wool, silk, cotton and linen. Oak bark can therefore produce colour without a mordant, although suitable fibre preparation and mordanting can improve consistency, depth and durability.

The colour is influenced by water chemistry and pH. Mildly acidic conditions generally produce lighter beige shades, while a moderately alkaline bath may deepen the colour towards brown. Iron provides a more controlled way to produce taupe, grey-brown, charcoal and brown-black.

At a glance

• Botanical source: Quercus spp.

• Plant part: Bark

• Origin: Poland

• Form: Dried and cut

• Colours: Golden beige, tan, warm brown, taupe, grey-brown and brown-black

• Fibres: Wool, silk, cotton and linen

• Tannin content: Naturally tannin-rich

• Mordant: Not strictly required, but recommended for improved consistency and durability

• Suggested quantity: Approximately 50–100% WOF

• pH sensitivity: Shade varies with water chemistry and pH

• Colourfastness: Good when suitably prepared, dyed and finished

• Vegan: Suitable for vegan projects

How much to use

Begin with:

50–100g oak bark per 100g dry fibre

Equivalent to 50–100% WOF—weight of dry fibre.

These results are guidelines rather than guarantees. The final shade depends on the oak bark strength, fibre, mordant, water chemistry, pH, extraction method, temperature and processing time.

Basic dyeing guide

1. Prepare: Scour the fibre thoroughly. Oak bark can colour fibre without a mordant, but suitable mordanting can improve consistency, depth and durability.

2. Soak: Cover the oak bark with water and leave it to soak overnight.

3. Extract: Heat the bark and soaking liquid gently at approximately 80–90°C (176–194°F) for two hours.

4. Strain: Strain the liquid through a cloth, retaining the bark for a possible second extraction.

5. Dye: Add the thoroughly wetted fibre and heat gently for approximately one hour.

6. Develop: Turn off the heat and allow the fibre to cool in the bath. Leave it overnight if a deeper shade is required.

7. Finish: Rinse thoroughly and wash gently with a suitable pH-neutral detergent.

Protein and cellulose fibres require different preparation.

Dyeing cotton, linen or another cellulose fibre? Find suitable preparation and mordanting methods here.

Working with pH

Oak bark colour is influenced by pH, although the result also depends on the fibre, water chemistry and individual batch of bark.

As a general guide:

• Around pH 5: Lighter golden beige and tan shades may develop

• Around neutral pH: Warm tan to medium brown

• Around pH 8: Deeper brown shades may develop

Adjust the bath gradually and test a small portion before modifying the entire dye bath.

Use a suitable diluted acid to lower the pH or a separately dissolved mild alkali, such as soda ash, to raise it.

When working with wool or silk, avoid high alkalinity, prolonged alkaline exposure and excessive heat.

Changes produced through pH adjustment may not remain completely unchanged through rinsing, washing or later exposure to a different pH. Iron provides a more controlled route when a darker result is required.

Adding oak galls

Oak galls can be added when additional tannin is required.

They may:

• Increase the total tannin content

• Deepen the response to iron

• Produce stronger taupe, grey and near-black shades

• Support the treatment of cellulose fibres within a suitable mordanting process

Oak galls are highly concentrated and should be added gradually. Sample first, particularly when iron will also be used.

Oak galls are sold separately.

Modifying with iron

Iron reacts strongly with oak bark’s tannins, shifting golden beige and brown towards taupe, grey-brown, charcoal and brown-black.

Use approximately 1–3% iron WOF in a separate, diluted afterbath. Begin at the lower end and increase only if necessary.

Where possible, use iron acetate, as it is generally gentler on textile fibres than ferrous sulphate used on its own.

Options include:

• Prepared iron acetate

• Carefully made iron water

• Ferrous sulphate combined with sodium acetate

Homemade iron water varies in strength. Test it on a small sample rather than treating it as a fixed-percentage solution.

Oak bark can react rapidly with iron. Observe the colour continuously, remove the fibre promptly and rinse it thoroughly.

Excessive iron may make fibres harsh, brittle or vulnerable to long-term deterioration.

Reusing the bark

Oak bark may continue to release colour after its first extraction.

Cover the strained bark with fresh water and extract it again for one to two hours. The second bath will normally be lighter but can be used independently or combined with another extraction.

Dry previously extracted bark thoroughly if it will be stored. Do not seal damp bark inside a container.

Tips from the dye pot

Colourfastness

Oak bark can produce good lightfastness and washfastness when the fibre is suitably prepared, dyed and finished.

Performance still depends on the fibre, mordant, bark strength, depth of shade, water chemistry, modifiers and aftercare.

Mordanting is not strictly required for every fibre, but it can improve the consistency and durability of the finished colour.

Iron-modified shades may appear darker, but excessive iron can damage textile fibres and should not be used simply to create an apparently more permanent result.

Wash finished textiles gently with a pH-neutral detergent and avoid prolonged exposure to strong, direct sunlight.

Storage and safe handling

• Store sealed in a cool, dry place away from direct sunlight.

• Dry previously extracted bark thoroughly before storing it.

• For textile dyeing and craft use only.

• Not for consumption or use in food, drinks, cosmetics or herbal preparations.

• Avoid creating or breathing bark dust and fine particles.

• Prevent contact with eyes, mouth and open wounds.

• Wear gloves and suitable protective equipment when handling dusty material.

• Wear gloves and eye protection when preparing mordants, acids, alkalis or iron solutions.

• Make pH adjustments gradually and monitor the bath with pH strips.

• Follow the safety instructions for all mordants, acids, alkalis and iron compounds used.

• Use iron sparingly, as excessive iron can damage textile fibres.

• Use dedicated dyeing equipment—never food-preparation utensils.

• Keep away from food, children and pets.

For textile dyeing and craft use only - not for consumption.

What you receive

Your chosen net weight of oak bark, supplied dried and cut in a pouch.

As this is a natural bark material, variations in colour, thickness, texture and piece size should be expected.

Mordants, acids, alkalis, oak galls, iron and other dyeing supplies are sold separately.

Packaging

We pack as sustainably as we can while protecting your dye materials. Pouch types may vary according to pack size and the availability of our preferred lower-impact options.

Display jars are not included.

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