Here is the indigo vat recipe that I have been working with written by Earth Hues. They are a wonderful company supporting agriculture, natural color and artisans around the world. I order my pigment from them and every time I order, I ask where the pigment is from. Most of the time the pigment has been from El Salvador. This is the recipe they provide and it's fantastic!
fan folded shibori
Kan ITO (Japan) 伊藤環 | bowl.
fabric dyed with rusty pins, onion skins, roses, eucalyptus and vinegar.
Itajime indigo from the Shibori Workshop. Full tutorials. via shibori workshop
Fabric dye - Non-fading Pokeberry Recipe - Pokeberry colors range from bright fushia to magenta to raspberry, and will last for several years by following this recipe. Over-dyeing fabric in indigo, once the pokeberry is set, will give purples. The berries are gorgeous, but fatally toxic. WEAR GLOVES!