Northern wolfsbane is one the earliest of the Aconitums to bloom - perhaps an adaptation to the short growing season in Scandinavia, Siberia, and Mongolia where it's native. The lavendar-blue flower stalks can reach over six feet tall, making them a striking presence in their mountain meadows, or the back of your garden border.

Aconitums are commonly known as monkshood, because the upper
sepal of each flower resembles the hoods of medieval monks. They
attract a variety of butterflies and moths, and are the primary food
source for Old World bees. Another common name, wolfbane, refers to the
poison made
from this plant's roots, which was used to tip hunting arrows.
Medicinal (and poisonous) uses of this plant date back to ancient times.
What's the difference between a medicine and a poison? Dosage.