The basic steps to natural dyeing
The best fabric to dye is a light, natural one like cotton, linen, silk and wool (preferably white).
Roughly chop up your chosen plant material. Place in a pot on the stove, then add water (about double the amount of plant material). Bring to the boil, simmer for 60 minutes, then allow the dye bath to cool to room temperature (this takes about 45 minutes). Strain into another pot, or use the same one.
The fabric needs to be pre-treated with a mordant so that the colour will set in the fabric, otherwise it will wash out.
Add the fabric for dyeing to the pot, bring to the boil again, then simmer for 60 minutes. Remove from the heat and leave the fabric in the dye bath until it attains the desired colour.
You will need a large pot to hold the dye and fabric. The fabric soaks in the dye for a time to get the right hue; the longer the soaking, the stronger the colour. The final colour will be lighter once the fabric is dry.