Eco printing is a multi step process that requires the fabric to be scoured (deep cleaned) before you can start to mordant and dye .
A mordant is usually a mineral salt ( for me at least) that the fabric soaks in a while and this opens up the fibers and lets the dye absorb better.
Once the mordanting is done, fabric can be laid out on the table and leaves can be placed on top.
Meanwhile in a bucket of a plant-based dye there is a flannel blanket the size of the fabric with the plants on it, this blanket has to be placed over the leaves and fabric, then all layers get rolled very tightly (without misplacing the leaves) on a flexible hose and rewrapped with string or strips of cotton. This bundle then gets put into a steaming pot for 2-3 hours depending on the fabric content and the size of the bundle.