Solar Dyeing - Part 2 Using your Solar Oven
I previously posted about creating my sustainable outdoor solar oven using reclaimed pallets and leftover house insulation materials.
A solar oven is a fabulous way to dye using artificial or natural dye sources as it bypasses the high energy consumption of a hob or microwave and replaces it with passive energy from the sun. Sustainable win!
I love to use my solar oven, particularly during the long summer months when the Scottish Highlands receives additional daylight hours due to our high Northern latitude. You don't need long hot sunny days for solar dyeing, but they will speed up and intensify the process.
Lets get started:
Start by preparing your yarn. You can soak in water or add a mordant which will improve the uptake of pigment and the longevity of the colour.
Some mordants will also modify or change the colour so do a little research before getting started.
You can learn more about the colours created by natural materials and the use of mordants in my book My Colourful Garden, from Loch Ness Knitting.
At the very least your yarn should be damp before use, if not it will soak up the water like a sponge without taking up any colour.
While your yarn is soaking gather up you fresh natural materials. I love to use tree materials for solar dyeing. Many tree bark, leaves and roots all make strong dye colours due to the presence of Tannin. To extract this colour on the hob requires high temperatures due to the solid nature of the material. Working with a solar oven requires patience but overall saves energy in the extraction process.
I choose to work with invasive and problem species to create my sustainable range of natural dye colours for the Loch Ness Knitting yarn collections. I encourage you to do the same, because you'll need at least 3 to 5 times the weight of natural materials for the quantity of yarn you plan on dyeing. So 100g will require 300 to 500g of natural materials.
This is because fresh natural materials are mostly water, but by working with problem or invasive species you can easily remove vast quantities of materials from your local environment in a way that is beneficial not harmful. You can also import traditional proven dye materials. I choose not to do this due to the carbon footprint of transportation and the impact of growing dye materials instead of food crops in vulnerable parts of the world.
Many common weeds such as Nettles, Dock, Sycamores and Rosebay Willowherb make excellent sustainable natural dye baths.
Chop your leaves, bark or tree roots into small pieces, 1-2" is a good size. Layer and mix up materials so you have some underneath your yarn and some over the top.
Cover with water, rain water is best as it is Ph neutral and natural dyes and very sensitive to changes in Ph.
Now cover with a lid and leave your container in the solar oven for anywhere from 1 week to 1 month. Be aware that the natural materials will be breaking down with the heat and the water to release the dye bath. This will mean the yarn is pretty smelly when it is ready. You'll need to give it a jolly good rinse and airing before you use it. For evenly dyed yarn you can open and turn regularly, for a variegated look leave the yarn alone and just see what happens.
This year I've had a beautiful selection of green, grey, orange, yellow and reddish brown from my solar oven yarn.
I'd love to see your results in the comments.