Lychnis coronaria

In message , told2b writes

There are plants which are perennials treated as biennials. But I wouldn't have put Lychnis coronaria in that category. The classic example is Digitalis purpurea (foxglove).

Some plants are monocarpic (that is, like annuals and biennials, they flower once, but take more than two growing seasons to reach flowering size). The best known examples are some Meconopsis (which, however, aren't consistently monocarpic) and Cardiocrinum. Lychnis coronaria definitely isn't monocarpic.

I would call Lychnis coronaria a short-lived perennial, but I might be misled by its relative intolerance of winter wet.

It usually behaves as a biennial.

It typically forms a rosette the first years and then flowers itself to death the second year without forming offsets.

The wet winters here never bother mine.