Ah, this is a South African native called Solenostemon canis (Coleus canina).

THANK YOU FRACTAL!! I seem to remember enquiring about this one's identity before too - just shows you that if at first you don't succeed, try, try, try again! :oD

It's supposed to keep cats away from your garden - that's why it's sold here, anyway!

I can see why, Spritz... :o}