Posted: 06/09/2013 at 17:33
Yikes ! don't try and propagate it! - you'll never get rid of it !
No really, Linaria purpurea or purple toadflax it is a lovely addition to the cottage garden.
I have the blue, white and pink forms - as nutcutlet rightly says they self seed very readily and you'll notice the pinky-grey new stems coming up in the spring like little bottle brushes.
If you really want more, gather the seeds in autumn, they look like buff coloured pepper corns and just scatter them where you want them. S'pose you could rake them in - I don't bother.