Yes, like most perennials the "sleep, creep, leap" rule seems to apply. I had read somewhere that the lobelia cardinalis is a short lived plant. But my 2 original plants are now in their 4th or 5th year, so that's pretty good, I think.
With the price of perennials, it's nice to wintersow them from seeds. It sure is a lot cheaper! And often healthier than what you find in the garden centers. Not to mention far more selection from seed than plants available locally. Occasionally I treat myself and buy a plant that I can't start from seed, but not that often any more.
Karen
