A natural dye often only really shines when its brother, the mordant, is part of the plan.

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POTASH (Potassium Carbonate K₂CO₃) ~ pH Adjuster & Scouring Agent

from €5,50

SODA ASH (Sodium Carbonate Na₂CO₃) – pH Adjuster & Scouring Agent

from €5,50

POTASH (Potassium Carbonate K₂CO₃) ~ pH Adjuster & Scouring Agent

€5,50

POTASH – pH ADJUSTER & SCOURING AGENT

Chemical name: Potassium Carbonate (K₂CO₃) | Grade: Textile | Use rate: 3–10%

No natural-dye studio is complete without potash (Pottasche in German). This alkaline powder (K₂CO₃) is slightly stronger than soda ash and is traditionally used to raise the pH of dye baths and indigo vats, scour cellulose fibres, and intensify plant yellows such as weld by increasing alkalinity.

💡 Note: This product was previously listed as Soda Ash (Sodium Carbonate). We have updated the listing to Potash (Potassium Carbonate) to reflect the correct material.

Uses

• Boost pH in indigo, woad, or fructose vats
• Add to your scouring bath
• Intensify weld yellow and other plant yellows
• Balance acidic dye baths when needed

In a nutshell

• Material: Potash (Potassium Carbonate K₂CO₃)
• Function: pH enhancer & cellulose scour
• Dose: 30–100 g · L⁻¹ (3–10% owf) dissolved in hot water or dye liquor
• Compatibility: All natural dyes; indigo & woad vats
• Packaging: Resealable moisture-proof pouch
• Safety: Wear gloves & mask; store cool, dry, and away from acids

Basic directions

Dissolve the required potash in hot water (or directly into a hot dye bath) at 3–10%. Stir until clear, then add to the dye pot or fibre scour. For indigo vats, add potash after the pigment to adjust alkalinity before introducing a reducer.

Safety & storage

Potash is strongly alkaline. Avoid inhaling dust and protect eyes and skin. Store sealed and dry; keep away from children and acids. Dispose of effluent according to local regulations.

💡 Tip: Pair potash with our Natural Indigo Powder or Indigo Kits for a complete dye setup.

Potash vs Soda Ash Table

Feature	Potash (Potassium Carbonate, K₂CO₃)	Soda Ash or Sodium Carbonate, (Na₂CO₃)
Alkalinity	Stronger	Milder
Best for	Indigo & woad vats needing a high pH	Controlled pH adjustment & cellulose scouring
Fibre use	Suitable for all natural fibres	Ideal for cellulose (cotton, linen, hemp)
Effect on dyes	Boosts colour strength (like weld)	Brightens plant yellows like weld
Traditional use	Historic indigo vat additive	General scouring & pH adjustments
Substitution	Can be used instead of soda ash for stronger alkalinity	Gentler option if potash is too strong

SODA ASH (Sodium Carbonate Na₂CO₃) – pH Adjuster & Scouring Agent

€5,50

SODA ASH – pH ADJUSTER & SCOURING AGENT

Chemical name: Sodium Carbonate (Na₂CO₃) | Grade: Textile | Use rate: 3–10%

No natural-dye studio is complete without soda ash (Soda in German). This alkaline powder (Na₂CO₃) raises the pH of dye baths and indigo vats, scours cellulose fibres such as cotton and linen, and brightens plant yellows like weld by increasing alkalinity.

💡 Note: Soda ash is milder than Potash (Potassium Carbonate), making it suitable for situations where a gentler pH adjustment is preferred. If you bought our 'Soda Ash' in the past, you would be looking for Potash, rather than this new Soda Ash listing.

Uses

• Boost pH in indigo, woad, or fructose vats
• Scour cotton, linen, hemp, and bamboo before mordanting
• Intensify weld yellow and other plant yellows
• Balance acidic dye baths when needed