Another experiment (in progress)... Solar Dyeing

Just over a week ago, I looked out of the kitchen window and saw... this:

The rhododendron in our back garden was in full bloom. What you can't really see here is the sole red rhododendron behind this wall of pinkish purple. I had planned to try out solar dyeing this year - so since the weather forecast looked fine for the next couple of days, I decided that now was the time.

I chose 1 hank of 100% wool yarn and one hank of 100% cotton yarn that had been cold mordanted over the past couple of days.

My guess was... extrapolating from what I have learned from earlier flower dye experiments (e.g. the roses last month)...  that the wool would again take on yellow hues... with a bit of luck, I might see something on the verge of green from the pink/purple flowers? But maybe I could get some faint pink or purple on cotton?

First step was picking flowers... lots of them - I picked 100 g of pink/purple and 100g of red for every 100g of yarn that I wanted to dye, which - on the first day, amounted to 400g of flowers over all. My daughters helped me, and I am pleased to say that the bees did not seem to be bothered too much. They minded their business, we minded ours - there were obviously enough flowers for everyone. Warning though: You'll end up with really sticky fingers.

Then I started to assemble my dye jars. It really was fun to layer the flowers and the yarn in the jars - starting with the red flowers, then yarn, more red flowers, yarn,... ,at one point mixing red and pink flowers, yarn, mixed flowers, yarn... pink flowers, yarn... ending with pink flowers. The jars were rather full when I was done...

Anyway - fill them to the brim with water, put them in the direct sunlight to heat them up... and wait what happens...

First thing that happened: I decided to fill a third jar the next day... this one with a wool / silk / ramie blend...
Second thing that happened: After just one day, I noticed the first colour changes.

There was definitely some green up in the pink/purple section... and there seemed to be a pinkish purple shimmer down in the red section - but it was too early to say which colours the yarns would pink up.

Third thing that happened: The weather changed. Towards the second half of the week heavy clouds appeared and decided to stay - they gave us some rain, which is of course good for the dye plants I'm trying to grow on our balcony - but what's worse: temperatures dropped below 20 °C... and have stayed there ever since. I am putting the jars into the direct sunlight whenever the sun decides to make an appearance (usually towards the evening)... but this project seems to have turned from a solar dyeing experiment to a low temperature dyeing experiment. Oh well... guess it'll just take a bit longer...
Here are my jars after one week - still looking promising enough: