Just an aside, at the moment I am conducting what seems an unending battle with a salvia that hasn't taken too kindly to the fact that I removed the original plant. This sage (probably Bog Sage) was growing with gay abandon and I decided to re-do the whole bed and start again; however, it has other ideas. Every little piece of root is regrowing and at least twice a week, and this is over a the last month, I have dug up pieces of the blasted thing. I think I may be winning, but I shouldn't speak too soon, as it is probably lying in waiting ready for the next round.

Thanks Anna, found the sites easily. I haven't time to go through it all thoroughly yet. I'm hoping to find some references to soil etc. I've fairly heavy soil where I planted this. It grew great guns, looking marvellous, then suddenly overnight it just up and completely karked it! Definitely not lack of moisture, not from heat. Possibly some sort of root rot? If that's the case it's not suitable for anyhwere I've got, so I doubt I'll replace it unless I can get more info that could suggest why it wasn't successful.