Primula mistassinica

Also known as the Mistassini primrose, Lake Mistassini primrose or bird's-eye primrose, this is one of the few natives to Canada and the US, where it is fairly widespread. It is however considered  quite rare in cultivation and endangered in places because of the destruction of its habitat. It is a lovely little plant that has mealy leaves with lavender-blue or white flowers. 

Culture: cool but well-drained situation. They will form vigorous clumps that are fairly short-lived in the garden. Good for growing in troughs.