Last night I stirred up some old indigo vats just to see if they would wake up. 

They had been sitting, I kid you not, for at least a year. 

This is the second iron vat that I've made, let sit for a few days and then gotten no color from. But then, after waiting a year (!), I've found the blue. I don't think this is typical for an iron vat.  

I'm glad I didn't give up on it. 

This is after just a short - less than a minute - dip. Really good color!

This is from the henna vat, not heated up, just stirred. I really love indigo dye. I've been playing with some other dyes too but I think I'll always come back to indigo.