Is there a trick to these? I know of a clump down the road from me in a sidewalk common area that bloomed heavily years ago but I have not seen in bloom in the last two years? I know it is a tight clump, perhaps dividing helps?
The clump Maryvonne gave me was large enough for two clumps so I do have two in my garden but one has never bloomed in the three or four years I have had it.
Cheers,
Sean