A few weeks ago I made some experiments with purple cabbage and blueberries for the workshop Childhood. Illustrated fieldwork.
Boiled cabbage, mixed with vinegar (left), soap (middle), and both (right)
Hues of blue from the various mixes
Purple cabbage (Brassica oleracea)
This pigeon was keeping an eye on my experiments 🙂
I borrowed some blueberries from my mother’s pot (she was making a delicious jam)
fresh blueberries, which were later crushed and boiled with salt to fix the color
Colors obtained from blueberry juice, after boiling with salt (left) and mixing with vinegar (right) or vinegar plus soap (middle)
Various shades of green obtained with sodium bicarbonate
sodium bicarbonate turns the purple juice into green
After three weeks, the colors obtained from purple cabbage (first row), blueberries (second row) and the illustrated bookmark (dark green turns into a yellowish hue)
ucuspucus pictorescus 
Foarte interesant, Raluca 🙂
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