I obtained the seed from a friend and each year he gets dozens of flowers. His plant which is in his jungle of a garden is several years old and I believe dies back like a herb each Autumn . It climbs up over his shrubs and he's been picking the blooms for the last couple of months.
I only ever planted a sweetpea once and noted that the following season it flowered -but with an apparently generic uniform colour. Does that happen to all or only certain species?? (First year was multi-coloured)