Part 1
The solar dye experiment jars I set up in January have had 6 months of “brewing” and have been emptied, rinsed and dried. You may remember I wanted to test whether the UV light has a significant effect on the final results or not. Check out January’s blog for more.

I carefully measured the dye stuffs and set up the solar dye jars; one in the garage in the dark and one on the window ledge in full day light. I have to confess I am surprised by the results, but that’s the point of doing experiments, to find out something….

Can you tell which skein was in the dark and which was in the light? No, neither can I!
Solar Dye Experiment, part 2
The same amounts of dye stuff and yarn were used for the second part of the experiment. This time one jar was put on the sunny patio for 6 months, and the other was in the shade under some shrubs in the garden. Once again, I’m surprised by the results!

Personally, I can see hardly any difference between the 2 skeins, though they are quite different from the winter ones for colour. The summer skeins are much more brown and less golden and rust than the winter ones. (The lovely willow tray in the photos is by Lin Lovekin.)
What does this mean?
The results are not what I expected at all and so I’m planning another set of experiments for the whole of next year:
- to set up 12 solar jars, leave them all on the patio and empty and wash one skein a month, then compare the 12 for colour over the varying lengths of time in the dye
- to set up the same experiment as this year and repeat it to see if the results are the same as this year
This learning if invaluable, but repeating the experiments will enable me to check the results from this year and draw more valid conclusions. What I can say is that solar dyeing is a great way to experience natural dyeing in an easy, low tech way and the results are very beautiful, even if they are unexpected.
These 4 lovely skeins will probably become a sample linen stitch poncho I am designing and working on.
Hello!
Your results are very interesting! I think this might show that temperature has an effect- I suspect that the outside summer jars may experience wider temperature ranges or higher ambient temperature which could be changing the chemical structures and therefore changing the end colours. Or it could also be the higher light levels (even in the shade) of the summer months. I’m a knitter and was a chemistry researcher & met you at Unravel this year. Looking forward to seeing your next set of results!
Thank you for your comments. I’m not quite sure how to eliminate the effects of temperature as well as the light levels, do you have a suggestion? I will be repeating the whole experiment next year and I’m happy to have 2 experiments going, one to eliminate light and another to eliminate temperature. Its all fascinating and valuable learning even if the results aren’t what I expected!