Thanks G. I'm trying it just that way as kind of an experiment in a terrarium setting. If it works it's going to be really beautiful. & I'm fairly confident it will work. Pings will grow just about anywhere & I've had really good luck with them. You may see it at the BACPS show in June ;-) cheers
http://en.wikipedia.org/wiki/Pinguicula_moranensis
scroll down, there's a great pic of p. moranensis growing on tree trunks...