The avocado pits were dried and put in a bottle with some water and are now out in the backyard taking in the sun. They'll probably be out there for a couple of weeks before I add any fabric to the mix.
I put the avocado peels in a stainless steel pot, put in some water and simmered for about 30 minutes. I then removed the peels, added ½ tspn cream of tartar and 1 tspn alum, and added the wet fabric pieces. I continued to simmer this mix for 15 minutes. I think I'm going to leave the fabric in the liquid for awhile, maybe even overnight. I'll show you the results sometime tomorrow. I have a feeling the color change is going to be very subtle based on what I'm seeing so far.