Immersion Dyeing is possibly the most widely used method of dyeing textiles. Basically, the dye is dissolved in enough water to immerse the fibres till the desired colour has been achieved.
Within this simplicity lies a large number of factors that will impact the final result, sometimes greatly.
Let’s start with the shape or form of the textile to be dyed, will continue with Temperature, Mordants and will discuss Over dyeing too.
Textiles
Gently whoosh in several changes of water. Squeeze out and remove from its mesh bag only after it is partly dry. Then pull it gently to smooth and groom the roving.
Yarns
Rinsed with an up and down motion to help remove tangles and smooth it.
Wring thoroughly, shake out and twist it while drying to soften.
Fabric
Can run through the right wash cycle, without soap, in a machine.
Temperature
Add textile to the dye bath and heat to about 60 to 90 depending on fibers for 1 hour or until desired color depth. Do remember that colour lightens after it is rinsed and dried. Silk should not be heated beyond 60 whereas cotton can easily heated up to boil point. All fibers, generally, should not experience sudden changes of temperature, and this especially true for wool – that is how felt is made : )
Cellulose fibres usually need double the dyestuff than protein base fibres.
When dyeing wool remember that needs at least 1 hr pre-soaking before immersing into the dye vat, and that the temperature of those baths should be very similar and only to be incremented gradually as needed.
You can leave the textile in the dye bath to cool down or remove and cool down outside, at any point, the longer you leave it the stronger the depth of shade. I sometimes like to experiment and leave certain samples for at least a month.
BEWARE, some dyes may perish within a few days, some will develop mould when left unattended, and some will stink up badly, fermentation is a regular occurrence. But some are fine, specially those with antibacterial properties, like dye extracted from the eucalyptus tree.
Mordants
Mordants are such an important concept when working with natural dyes. Visit my post on Mordanting for more detail instructions.
 The use of iron, copper, or some other metal pot/vessels as mordants is traditional during immersion dyeing to shift, change and improve the light and wash-fastness of many fabrics. There is scope for lots of experimentation and one of the safest way to use mordants in your colour searches.
Iron turns golds to moss greens, reds to plum and maroon, darkens browns, and makes beautiful grey shades to black together with tannins.
Many leaves and plants will make grey with iron as the only mordant needed.
When using mordants and dyeing in low temperatures, or as with solar dyeing, you will need to ensure that the dye bath reaches a warm temperature which is when the chemical reaction between the plant-based dye stuff and the mineral mordant takes place.
Over dyeing
Remember that the dye colours will change the base colour. When combining two colours, we start with the lighter shade and add the darker one slowly until the desired result is achieved.
With some specific dyes to achieve darker shades is better to add a second mordant step to the fabric before adding to a second dye bath.
