Dyeing Golden-Brown with Wattle Bark — The Australian Acacia Tannin Dye

Use 100% WOF of dried wattle bark, or 20-30% WOF of wattle bark extract. For 100 g of wool using raw bark, weigh out 100 g of dried, broken bark pieces. For extract, weigh out 20-30 g. Black wattle (Acacia mearnsii) bark has the highest tannin content. Golden wattle and silver wattle also work well. Break bark into 3-5 cm pieces. Wattle bark extract is sold as a dark brown powder by tanning and dye suppliers.

Place the bark pieces in a dye pot with 4 litres of warm water and soak overnight (8-12 hours). The water will turn a deep golden-brown rapidly — wattle bark releases tannins faster than most bark sources due to its extremely high tannin concentration. By morning, the liquid should be a rich, dark amber-brown. If using extract, simply dissolve in hot water — no soaking needed.

Bring the pot to 80°C and hold for 45 minutes. Stir occasionally. The liquid will deepen to a very dark amber-brown. Wattle bark extracts fully within this time. Do not boil — gentle heat produces cleaner, more golden tones.

Strain the dye liquor through a fine mesh strainer into a clean pot. Press the bark to extract all remaining liquid. Bark fragments will tangle with wool — strain thoroughly. The strained liquor should be a rich, clear golden-brown to dark amber.

Pre-wet wool in lukewarm water for 15 minutes, squeeze gently, and lower into the wattle bark dye bath at room temperature. Slowly raise to 80°C and hold for 45 minutes. Turn gently every 10 minutes. No mordant is needed — wattle tannins are substantive and bond directly to wool. The wool will develop a warm golden-brown to amber — lighter and more golden than quebracho, darker and warmer than eucalyptus. The colour has a distinctive luminous warmth.

Turn off the heat and let the wool cool in the dye bath overnight. Remove, squeeze gently, and rinse in lukewarm water until the runoff is mostly clear. The final colour is a warm golden-brown to rich amber — the colour of the Australian bush in afternoon light. Washfastness is excellent. Lightfastness is good. Iron modification shifts the colour dramatically toward dark olive-brown. Wattle bark also serves as an excellent tannin pre-mordant for cotton. Dry in shade.