This is an almost ridiculously simple method of dyeing cloth or fibre, which can even be used on greasy wool direct from the sheep. It is a process that requires that most precious of ingredients, time. On the other hand, little intervention is required once the dye-pot has been set up. Be warned, though — the process will test your patience as you burn to investigate the exciting things happening in your containers.
The equipment required is laughably simple; merely as large a collection of jars with lids as you can muster. The beauty of the process is that the jars do not even need to be rinsed in advance, as remnant jams, pickles and sauces can all act as interesting mordant adjuncts. Solar dyeing is another way of using up fabric scraps and ends of dye baths, or small handfuls of dye-stuffs that are not worth boiling up, as well as being a simple path to colour if you don’t have time or space for the more complicated dye processes.
If planning to leave the jar for an extended time, place a small stone on the fibre being dyed to weight it down so that the contents do not break the surface, and pour a quantity of melted wax into the vessel. This will prevent mould growing on the dye, and even though the wax may melt in the heat of the day it should remain impenetrable to air. (To recycle the wax, empty out the contents when they are cool and the wax is solid.)
When your patience has been exhausted, open the jar. Pour off the liquid (which by this time will retain little if any colour) and rinse the fibre in lukewarm water. If you have a lot of small scraps, place them in a netting washing bag and machine wash on a gentle cycle. Then simply hang the whole bag somewhere in the shade to dry.
If there is visible mould, place the jar (with the lid loosened to allow for the expansion of the contents once frozen) in a plastic bag in the freezer for a week to kill the mould. Then thaw and rinse in the usual way.
The variations on this simple method are limitless. Roll up dried eucalyptus or mistletoe leaves (fallen under the tree) in the cloth itself, stuff into jar and pour water (or left-over tea, or cold coffee, or the liquid from pickled beetroot) over the top, seal and leave. Try this with any natural fibre, and with almost any plant available (keeping in mind the guidelines for responsible collection).
It is an especially good process for the tougher-leaved varieties (be advised that delicate flowers do have a tendency to rot). The less water, the more interesting and defined the patterns on the cloth will be, resulting in exquisite fragments for use in embroidery and patchwork.
Remnant dyes can be used to dye sliver for felting, threads for stitching, and multi-hued yarns for knitting and weaving.
Use the solar-dye technique to extract colour from flowers by cramming a jar with blooms, covering them with water, sealing the jar and then allowing it to stand somewhere warm until the liquid is a pleasant colour. Strain and use as desired.