Different herbs, mosses, lichens, barks, berries, twigs and leaves can be gathered at different times of the year to make natural dyes. Dyeing with plant materials in an ancient and rewarding craft; it is full of surprises as you never quite know what colour you are going to get- it all depends on the freshness and concentration of the plant materials, the type of fabric you use, and the mordant (fixative) you use. The colours are softer and more subtle than chemical dyes, and can help you feel like part of the landscape.
For the ancient Celts, dyeing was a magical process, a women’s craft with strict taboos on dyeing fabric in the presence of men.
Mordants
Most natural dyes need a mordant to make them fast. The word derives from a French term meaning ‘to bite’ and it refers to a chemical applied to the fabric before dying that helps the dye adhere to the cloth and fixes it so that it doesn’t wash straight out again. Some are poisonous and should be handled carefully. Always wear rubber gloves and work in a well-ventilated space. Mordants can be obtained from pharmacies, specialist craft and dye suppliers.
Alum (aluminium potassium chloride/ potassium aluminium sulphate)
This is probably the most popular mordant, and works with a wide variety of dyestuffs. In the past it was obtained from stale urine, wood ash, oak galls, oak and alder chips and burnt seaweed. Alum brightens the colour of the dye. It is often combined with tartaric acid to produce fresher, clearer colours. Use 1 oz for every 1 lb. of dry fabric weight. And add 1 oz cream of tartar. Dissolve, add 2 gallons water, bring slowly to the boil, add the fabric and simmer 1 hour. Remove the fabric and drip fairy dry, now begin the dying process.
Iron (ferrous sulphate) or copperas
The ancients obtained this from bogs and iron ore. It makes colours more muted, or ‘saddened’ to use the correct term. Use 1/8 oz for every 1 lb. of dry fabric weight. Otherwise, boil the fabric first with the dye for 30 minutes. Lift it out. Ass ½ oz ferrous sulphate and 1 oz cream of tartar, ready dissolved, to the dye pot. Replace the fabric and boil for another 30 minutes.
Copper (copper sulphate) or verdigris
This is used to give a blue-green tint to a colour. Use ½ oz with ½ pint of vinegar for every 1 lb. of dry fabric weight. NB: Poisonous, handle with care!
Tin (stannous chloride)
For each 1 lb fabric add 1 oz cream of tartar and ½ oz of tin crystals. Dissolve them together in water and add to 2 ½ gallons of water. Heat and add the wet fabric. Bring slowly to the boil, reduce heat and simmer 1 hour. Take out the wool and let it drip fairly dry. You can now begin the dying process. Tin will brighten colours. Use ½ oz for every 1 lb. of dry fabric weight. NB: Poisonous, handle with care.
Chrome (potassium dichromate)
For each 1 lb fabric add ½ oz potassium dichromate. Dissolve them together in water and add to 2 ½ gallons of water. Heat and add the wet fabric. Bring slowly to the boil, reduce heat and simmer 1 hour. Begin the dying process straight away. NB Highly poisonous, handle with care. Use with the lid on the pot as the fumes are highly toxic. Always use rubber gloves when handling the material.
Substitutes
Simple household substances as vinegar, bicarbonate of soda, cream of tartar, and wood ash can provide a practicable and greener alternative. They will not produce a completely permanent dye but will greatly reduce fading.
Preparing the Fabric
Natural dyes work best on natural materials such as cotton, silk, and wool. Although a natural fabric, linen takes dye less readily than other materials. Rayon is the only synthetic fabric with which natural dyes can be used successfully.
It is best to keep your dyeing utensils separate from your cooking ware, as some of the substances you will use are poisonous. Copper or brass kettles are reckoned best, though enamel is fine and obtainable from second hand shops- never use aluminium- clean them afterwards with white vinegar and a little sand for scouring. You will also need a plastic bucket to rinse the fabric, muslin for straining out the plant material, stirring sticks, measuring jugs and scales, a stove for heating the liquids, the dye plant material and mordant.
The fabric should be thoroughly washed and soaked overnight if necessary to remove residues of grease, preferably in rainwater. Give it a final rinse in warm water to which a tablespoon of vinegar has been added.
Adding the Mordant
If you are using a mordant it should be added at this stage. The mordant should be dissolved in a small quantity of hot water, and a further four gallons of water gradually added. Totally immerse the fabric in the liquid and gradually bring to the boil and simmer for an hour. An alternative method is to soak the cloth in the mordant mixture for twenty-four hours (though if using alum, it will need to be boiled). Remove the fabric from the solution and dye it immediately.
Dyeing the fabric
Use approximately 2 oz of the plant material for every 1 oz of fabric. The plant should be chopped or crushed place it in a large pan and bring to the boil. Simmer ½ -2 hours depending on the material- flowers will give up their colours quickly, while woods take longer. Turn off the heat and leave to cool a little, then add the fabric, bring back to the boil and simmer, stirring, until the fabric takes on a good colour. Wearing rubber gloves, rinse the fabric several times, gradually decreasing the temperature of the rinsing water. Hang up the fabric to dry naturally. You can repeat the dyeing process two or three times to increase the colour density of the fabric and improve its resistance to fading.
Plants to Use
Most plants will produce some kind of dye, but ‘tinctorum’ or ‘tinctoria’ in their Latin name indicates a plant that is long established as a dyestuff. Various parts of the plant can be used- bark, berries, flowers, juice, leaves, shoots, or roots, depending on the particular plant. See the dye table.
Dye chart
Plant colour mordant
Alder bark red-brown alum
Alder flowers green alum
Alder twigs brown iron
Alkanet beige alum
Apple bark green iron
Bilberries blue iron
Bilberries purple alum
Bilberries blue iron
Privet leaves blue alum & salt
Birch bark purple iron
Blackberries light grey alum
Blackberry shoots black iron
Bayberry leaves yellow- brown alum
Parsley green-yellow alum
Birch leaves green-yellow alum
Apple bark red-yellow alum
Madder dark red alum & tartar
Bed straw roots red alum & tartar
Walnut leaves brown alum
Iceland moss light brown none
Elder bark black iron
Blackthorn orange alum
Elderberries purple alum
St John’s wort flowers purple none
Agrimony yellow alum
Ash inner bark yellow alum
Birch yellow alum
Bog myrtle yellow alum
Broom yellow alum
Marsh marigold yellow alum
Meadowsweet yellow alum
Nettle yellow alum
Crab apple bark yellow alum
Bracken yellow alum
Flag iris blue iron
Dock beige alum
Dyer’s weld green chrome
Elder berries pink-purple alum
Elder leaves yellow alum
Elder shoots green chrome
Golden rod yellow alum
Gorse yellow alum
Heather beige alum
Horsetail green alum
Indigo blue none needed
Lichen yellow to purple none needed
Lily of the Valley leaves green-yellow alum
Madder root orange-red alum or iron
Marigold brown alum
Oak bark brown alum
Oak bark yellow tin or zinc
Oak bark black iron
Onion skins yellow alum
Pine red-yellow alum
Pine cones beige alum
Sloes purple alum
Sorrel leaves yellow alum
Sorrel root red alum
Sunflower petals yellow alum
Walnut shells brown alum
Woad green-blue none needed
© Anna Franklin, Hearth Witch, Lear Books, 2005
Hearth Witchery 
Great post! I’m going to save it to refer to later on!
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