I discovered these techniques when I did a VEGETABLE DYEING workshop with Fabienne Ray in the south of France. She herself learned these techniques from India Flint, an Australian textile artist who creates magnificent works with eucalyptus leaves.
VEGETABLE DYEING is a process where leaves, flowers and other plant materials are used as the source of color in the dye bath. So many leaves and flowers make fantastic colors! 
Before putting the fabric in the bath, it can be folded in different ways, where parts are hidden they will remain white. You can find so many different techniques on the internet.

ECO-DYING is India Flint's specialty. When the leaves are positioned on the fabric,  the fabric is wrapped very tightly around a stick and soaked in a bath of simmering plants. The impressions left on the fabric are due to the tannins in the leaves.  Some leaves such as eucalyptus leave magical designs on the fabric and the colors depend on several factors such as the mordanting of the fabric (we opens the fibers), the metal of the tank, etc... 
Currently I really like to use vegetable dye together with my screen-printed images. Working with natural dye means creating direct contact WITH NATURE. There are always surprises, nature speaks to us. 

In 2019 I also did a workshop with Irit Durman, using a little different technique to keep more of the colours of the flowers and leaves.

Dyeing INDIGO and PASTEL is very different, but just as magical! 
When the fabric is taken out of the vat, it comes into contact with the oxygen in the air and the color changes from yellow-green to these wonderful shades of blues.

I created collections with PASTEL for the company  PASTEL LAND.  
 
Wonderful textile artists use this natural dyeing technique:

Lotta Helleberg

India Flint