We have all had the occasional raspberries go rancid in our fridge, and usually these make their trip to the trash or the compost pile, but you can use these for dying fiber. The color will not be as bright, but it is a great way to get earthtones, or add color to fiber you are already dying. This method involves no mordants, so I don't know what you would get with a mordant.
Step 1: Put
fruit into pot on stove with 1-2 cups water. Mash fruit with fork or potato masher and bring to boil for 30 minutes.
Step 2: Allow to cool on stove until you can work with the liquid
Step 3: Strain liquid to get rid of berries, seeds, etc.
Step 4: Pour into dyepot and add water.
Step 5: Add fiber to the dyepot in addition to 1/2 cup vinegar
Step 6: Turn heat on dyepot and allow to simmer for 1-2 hours, or until dye is absorbed.
Step 7: Rinse out fiber and allow to dry.