> According to Robert Beer:
> >
> > Question: you had one plant of one species affected
> >but not the others;
[stuff deleted}
>
Anytime that one plant of a species is having a non-trivial problem that
is not affecting others of the same species, I suspect that a rhizome
borer may be at work. You can remove the plant from the growing mix and
visually inspect the rhizome for damage. If you see indications of a
borer, carefully cut down the length of the rhizome with a CLEAN, sharp
knife so as to split it lengthwise. If a borer is present, you can
extract it and send it to borer hell. Then you can repot the two halves of
the original rhizome and perhaps have two plants in a few months if they
both establish successfully.
- Carl