ANISE HYLLOP : Agastache foeniculum
Escaped introduced plant.
Also called blue giant hyssop.
Looking quite simillar to some of our native plants, it is unsurprising that this one has not been as readily noticed. Although it has a mediterrean relative, it actually originates from North America.
Wikipedia tells us that Anise hyssop was used medicinally by Native Americans for cough, fevers, wounds, diarrhea. The soft, anise-scented leaves are used as a seasoning, as a tea, in potpourri, and can be crumbled in salad. The purple flower spike is favored by bees who make a light fragrant honey from the nectar.
Our example comes from the Leven towpath in mid-July.