Salvia roscida aka Salvia fallax
Have been growing this Salvia in pots for several years. At first it used to flower brilliantly in frost-free conditions under glass, in late winter. But for the last 4 years....nothing. I have kept plants pot-bound, repotted others, take cuttings every summer, kept some dry, fed and watered others, still with no success.
Suspect that the last 3 winters in the UK may be the cause of this, as they have been particularly dull and cold, but never any frost in the greenhouse. You can see how this Salvia can be magnificent by looking at Rolando's site
Hope to meet some of you at the summit!