Good, Helena, I was going to ask if anybody had a Gautier about. Actually, I've thought that so long, that I would be willing to bet that it was identified as asphodel by Agnes de Mille, and I should know better by now! I know I've been familiar with the plant since before I was 15 years old, because I remember discovering the word in some intentionally bad poetry written by W.S. Gilbert for the opera
Patience. I know that I first read the score and libretto for that opera when I was fifteen, and I was already familiar with that word, and was surprised to see it.
And yes, rosemary is the herb for remembrance:
Ophelia:...there's rosemary, that's for remembrance, and rue....
Rosemary is a tender perennial, and a house plant in northern Europe more often than a garden-dweller, so maybe somebody was just adjusting the plant to the climate.