What You Can't Dye with Food Coloring

In my various yarn dyeing videos and tutorials, I always mention what you can and cannot dye with food coloring, and I decided that it was time to actually show what works with these methods.  In the following video, I attempt to dye 100% wool, 100% cotton and 100% acrylic yarns in one pot.

As expected, the 100% wool took up color extremely well and the 100% acrylic yarn did not take any color.  Surprisingly, the cotton obtained a stained appearance that I was unable to wash out during the course of filming.  In comparison to the wool, the cotton received significantly less color.  There are much more reliable methods for dyeing cotton to get vibrant colors (such as a Tulip Tie Dye Kit) and I would recommend trying these rather than wasting a lot of food coloring and vinegar.