Fibers and Dyes eye each other warily.

Something else you should know about dyes. Different dyes are meant for different fibers, and even while you can theoretically use the Fiber Reactive Dye, it's not necessarily going to end up the color you planned. Above are a skein of handspun wool and a silk scarf, BOTH dyed from the same container of moss green... one of these things is not like the other!

Time to get some acid dyes for wool...