Natural dyes are beautiful and aesthetically pleasing. Each natural dye colour is made up of several molecules of colour. Where chemical dyes are usually one colour molecule or just two colour molecules, natural dyes contain many colours in each colour that our eyes see. This is why with chemical dyes, when we put two reds together that don’t match, it jars our sense of beauty. We say it clashes. Not so with natural dyes. All natural dyes go together because of the many colour molecules in each colour. There’s a biochemical reason for this. Each plant or insect colour has several chromophores that make up the colour that we see. Which chromophores adhere to your cloth can be shifted by changing the pH of the liquid that you extract the colour with or by adding mordant salts or metals to the cloth, such as alum, calcium, magnesium, iron or copper.
I recommend planning your garden around both perennials and annuals, with a thought to the colours that each plant gives. Aim to have the three primary colours – blue, red, and yellow – represented in your garden in abundance. From these the full rainbow of colours will be available to you.