vipers bugloss is the same root as is used to do the alkanet powder and it grows wild up into the high country where I go hunting. It is not a large plant and I contemplated getting a few of the roots to try, but the moment passed as I wasn't sure what the process would be to turn it into a usable product.

http://www.luontoportti.com/suomi/en/kukkakasvit/alkanet