see this thread http://davesgarden.com/community/forums/t/853182/ it might help?
Germinating Stevia (Sweet Herb)
Have realized it comes up from the roots -- I have several little stevia plants coming up about a foot from the original, so I think once you've established it, you HAVE it. Nice.
Stevia roots really easy from cuttings, will root in about 2 weeks. I sell these in my greenhouse and can not keep enuf of them. People are just now trying this plant, especially diabetics.
Pam