Final result with madder
Following on from my blog ‘Make the Most of Your Madder – Part 1’ (February 2023) I wanted to try the alkaline method of extracting madder dye, as explained in Jenny Dean’s book ‘Colours From Nature’. For me Jenny Dean is the Delia Smith of natural dying; easy to follow, reliable and with delicious results!
The advantage of this method of dyeing is that it can be done without heat and without the use of an alum mordant. Most tap water has a neutral pH of around 7. The extraction method works by raising the pH to 9 or 10 with the addition of soda ash, or in this case wood ash water that I made using ashes from a log burner.
(More information on pH levels and their use in natural dyeing is available through the online natural dyeing course, see www.elkatextiles.co.uk)
As always I used four different plant (cellulose) fibres: natural linen, bleached linen, natural banana yarn and squares of bleached cotton fabric.
I also used skeins of naturally white Bluefaced Leicester wool. Wool is an animal (protein) fibre.
I used two sets of each; one set was just scoured (cleaned) and the other was scoured and mordanted with alum – about 150g in all.
I used 100% WOF (weight of fibre), so an equal weight of fibres and dried madder root.
To prepare the alkaline solution you need a bowl or pot big enough to hold the solution and the fibres to be dyed. The alkali used can be either soda ash (washing soda) or wood ash water. It’s important to have some pH testing paper strips or, if you have one, a digital pH reader.
Testing with digital pH tester
It took 100ml of wood ash water to raise the 2 litres of water to the right level; just under pH10 according to the more precise digital pH reader.
Adding madder to alkaline solution
The madder root was then added to the alkaline solution, stirred well and left to steep for a couple of days before testing the pH again.
Spoon showing developing colour and low pH paper
As the madder begins to ferment, the alkalinity will start to fall, so it’s important to test the solution regularly. Allowing the pH level to drop will result in more orange tones.
Add more wood ash water as necessary to keep the pH level up. I left the madder to steep in the alkaline solution for a week in all, though good results may be obtained in less time than this.
To strain the dye bath you need a sieve lined with a fine muslin cloth (or old net curtain). Make sure you strain the dye into a clean bowl or pot to avoid any bits sticking to the fibres when you enter them.
Adding fibres to the dye bath
It is easier to get even dye results on yarns than it is on pieces of fabric, which tend to fold over on themselves. The folds and creases dye unevenly (see blog Natural Dyeing With Nettles, June 2023) so when entering fabric into a dye bath try to minimise these. With larger pieces of fabric, such as a T-shirt, it’s necessary to keep working the fabric around in the dye bath, and lifting it in and out to make sure the dye is reaching all surfaces evenly.
Hanging fibres to dry
Allow the fibres to dry before washing them as this allows the dye to penetrate further and to fix in the fibres.
Wash the fibres gently in warm water with a little pH neutral detergent.
Continue rinsing the fibres until the water runs clear, or almost.
The non-mordanted plant fibres have dyed to pretty shades of dusky pink (top).
The mordanted plant fibres have dyed to a coral orange (bottom). This is due to the acidic nature of the alum mordant in the fibres that has lowered the pH level.
Because of the unique structure of wool, with its outer scales and inner cortex, I decided to heat the wool in the dye bath to about 80C to allow the colour to penetrate the fibres fully. Jenny Dean warns against this as a heated alkaline solution can damage animal fibres. The result is that both the mordanted and non-mordanted wool skeins are very similar in colour.
Contrasting cotton squares
It’s worth noting with the cotton squares that the mordanted sample has dyed more evenly than the non-mordanted sample. Pale pinks can be achieved with madder root on mordanted fibres by using a weak, partially exhausted madder bath – see Make the Most of Your Madder – Part 2.
But mordanted or not the colours are all lovely - delicious, in fact!
Jenny Dean, Colours From Nature – A Natural Dyer’s Handbook, 2008
Boutrup and Ellis, The Art and Science of Natural Dyes – Principles, Experiments and Results, 2018