The Banana Vat
The banana vat is the most popular of the fruit vats. It is reliable, gives a clear bright blue, smells good, and is fun to make.
Review the instructions for indigo vats. Don’t forget to scour your cloth or yarn before dyeing.
For a vat of about 20 litres
— 75 g (2.5 oz) powdered natural indigo
— 3 kg (7 lbs) sweet, over-ripe bananas (2 kg (5 lb) if peeled).
— 75 g (2.5 oz) calx (calcium hydroxide).
Peel the bananas and discard the peels. In a saucepan, mash the bananas well, cover with a generous amount of water and boil for 30 minutes.
Fill a 20 litre (5 gallon) stainless steel vat 3/4 full with hot water.
Filter the juice from the boiled bananas and add to the water in the vat.
Keep the mash and cover with water. You may need to reheat this and strain off more juice later to adjust or revive the vat.
Add the indigo to the vat. Sprinkle on the surface of the vat and stir in until well mixed.
Add half the calx (reserve the second half if you need to raise the pH). Sprinkle on the surface of the vat and stir the vat gently. Do not whip it. You do not want air in the liquid. Wait for a few minutes. Then stir again. Repeat this stirring three or four times.
Heat until the liquid reaches 50°C (120° F). You may then turn off the heat. Leave the vat covered overnight. The next day the vat will have a bronzy surface and a dark blue indigo flower. The interior of the vat will be a clear yellow green.
Follow our How to Dye With Indigo instructions.
