Botanical Colours

River Diary

To test my new colours I have been making drawings at high tide of the patterns in the Rver Tay as it flows passed the bottom of our garden.

The river mud means there are days when it all looks golden and on other days the light is silver, the colour also changes as you get closer to the water.

I use the patterns to record the effects of inks made from food waste, garden plants and weeds. Dock roots,nettles,New Zealand flax seeds,coreopsis flowers,pomegrante, and avocado skins and stones.

I have also purchased black walnuts, indigo, oak galls and cochineal as I am unable to grow indigo here on the east of Scotland and black walnuts don’t seem to grow in the uk I’ve only ever found a few oak galls locally.Cochineal generally from Peru can be bought as extract powder,or whole dried insects.

The colours react with each other especially the oak gall when it is mixed with ferrous sulphate, the ink visibly changes on the paper becoming darker and darker. Very little ink is required to make a grey wash.

I have some tests to make re the lightfastness of colours, effects of different papers, treating paper with a mordant and ink storage.

I have successfully made indigo watercolours with the addition of gum arabic.

Honey can be added to help the paint retain moisture and re-wet after drying. Honey is also a natural preservative and a plasticiser, it therefore increases the flexibility of gum arabic and prevents cracking in the palette after drying. Runny honey is best.

Like honey, glycerin is a humectant and a plasticiser which can be bought at a pharmacy, it is less sticky too.

Clove Oil is a natural antibacterial and antifungal agent, it is an excellent preservative which stops the paint going mouldy.

Sketch book records.

Main Picture : oak gall and indigo,

From top left: 1. avocado, dock and walnut, 2. avocado, 3. coreopsis with soda ash and NZ flax,

4. coreopsis, walnut and Herebin ‘gris de nuage’ , 5.Indigo and coreopsis.

Making ink from plants and pigments

To make ink you can use seasonal plants and waste food with a small amount of water, reducing it down and then adding a binder and a preservative.

Materials can be fresh or frozen and some ideas are avocado rinds, tea leaves,coffee grounds,berries,nettle leaves,dock, dandelion, and iris roots or any other dye plants.

Drawing Ink

What you need;

Plant material or dye powder

Measuring cup/spoons

Gum arabic



Heat source




Just cover the plant material with water, it’s important to use the least amount possible.

Simmer for 30 mins for an hour, sometimes I leave it to soak overnight.

Or you can leave the material covered in a pot with a lid for several weeks.

For both processes once you have a good amount of colour in the water , strain the dye bath with a seive to remove the plant material.

Then place the pot over a low heat and reduce the liquid until you have a syrupy consistencey.