Red and white varieties of red valerian growing at the curb
The Latin name for our friend red valerian is Centranthus ruber. You can see plants with red or white flowers. Oddly enough, even species with white flowers are still considered Centranthus ruber (ruber means red, in case you didn't know).
Close-up of flowers of red valerian
The flowers are fairly small and grows in (typically) round clusters. The flowers have peculiar shape which makes plant easy to identify. The leaves are opposite. Presumably the plant is edible (leaves and roots) but I haven'r tried it yet. Unlike true valerian, this plant is not considered to be medicinal.
White form of red valerian
Centranthus ruber makes an excellent garden plant. It attracts pollinators like bees and butterflies, takes minimum care and is attractive to look at.