Mordants
Before dyeing your fabrics they are often treated with a mordant solution. A mordant helps to fix the colours: in everyday terms it bites into the fabric and gives the natural dye something to fix on - indeed the word mordant means 'cutting' or 'biting' in French.
Not all natural dyes need mordants as they can be strong enough to fix to the fabric without the need of something to fix them. Onion skins, turmeric and tea are all such dyes and if you have ever spilt a curry or a cup of tea down a white garment then you have seen one of these dyes in action.
There are a wide range of different substances that can be used as mordants and some are fairly toxic. However, there are plenty that most people will feel comfortable with, including vinegar, salt and not so common substances such as alum. Alum is shorthand for aluminium potassium sulphate, which is used in the manufacture of baking powder.
Madder (Rubia tinctorum) has been the plant of choice when creating a red dye over the last 5000 years and traces of madder dyed linen were found in the tomb of Tutankhamen. The vivid red colour from madder dyed clothes has meant that it has always been a popular plant when home dyeing.
As it is the root of the plant that is needed, it will be difficult to source from the wild, therefore madder is best grown from seed sown in springtime. It then takes about three years for it to reach its maximum yield. If you can't wait that long then you can buy some online at a fairly reasonable price.
To make a madder dye, first dig your roots and wash and chop them. Then place 350g of freshly harvest roots, or 50g of dried, into water for 24 hours. Unfortunately, you will need to then discard this water and cover the roots again with 5 litres of fresh water.
Grab a hand blender and blend all of the roots. The next step is one familiar to any home brewers as you will need to ferment the dye. As you don't really want to dye any of your home brew equipment, it is best to use a separate bucket with a lid for this job. (It is also good practice not to mix equipment used for foodstuffs with home dye equipment). Or you could just tie a plastic bag to an old bucket. Leave this for a week.
Soak the yarn or garment in an alum mordant for three to four hours. Strain the liquid from the bucket using a sieve and compost the mush. Leave your garment in the strained liquid for a couple of days, and voilà it will have turned red!
Yellow dyes
The decline in the use of artificial colourants due to their toxicity in
food and textile industry, put forward by international market has
increased the importance of natural raw materials. From those, pomegranate
peel (Punica grantum) with solid applications is one of the
most important sources of natural dyes. The major colouring component
in pomegranate is tannins, extracted from the fresh and dried peels.
Yellow is perhaps one of the easier dyes to obtain naturally. It can be obtained from a variety of sources including onion skins, tumeric, cold tea and rhubarb. Or if you would like to obtain it from the wild in can be extracted from tansy, the aptly named dyers chamomile and from dyers greenweed.
To extract the yellow dye from the above plants, cut up your plants and stand them in cold water for 24 hours. Then boil for 1 hour. You will need roughly 9 litres of dyed water for 250g of wool. Ensure that the colour is vivid - if not, add more of your plant material and then strain. Dip the wool or garment into the warm solution and leave overnight to dye. If using tumeric or onion skins (although onion skins are not that vivid) you won't need a mordant.
