Janet Tweedy writes

Kay, I dug a cutting of a very double Lychnis out of the gravel and the
nursery in Berkhamsted. The owner said it was a spare seedling from
lyhcnis he had.
Was taller than most and the flowers are very pretty (gone over now)

A double Lychnis flos-cuculi or double one of the other ones? I must
admit I prefer the single L flos-cuculi (Ragged Robin) - the delicacy of
the deeply divided petals is hidden when the flower is double.
--
Kay