Step two

After following the steps of the Natural dye with Japanese Knotweed recipe, sieve the dye bath leftover and reserve the liquid to make the pigment.

Step three

Pour the dye bath in a silicone tray. If your tray has more than one compartment, fill each one up to 1 cm in height (* The quantity of dye bath it will depend of the size of your mould. As the liquid needs to evaporate, I would not recommend to fill each compartment with more than 1cm of hight).

Step four

Put in the oven 150 degrees Celsius for approximately one hour but the time may vary depending on the oven.

Step five

When the liquid has evaporated, turn off the oven and remove the tray from the oven. Let it cool down. The colouring will be dark brown.

Step six

Scrape the leftover with a teaspoon and grind it in a mortar and pestle.

Step seven

Sieve the powder and store the pigment in a sealed glass container.

Step eight

The pigment is ready. Pour some of the pigment on a porcelain saucer, add a few drops of water, stir it and your watercolour ink will be ready to be used on paper.