campanula rapunculus

rapunzel plant

A kind of purple bellflower, I wonder how Grimm brothers could write that Rapunzel's mother had drooled over this plant during her pregnancy. I mean it is flowering plant, bell-shaped, with purple color. Must say looks a little toxic to me.

By the way how did ancient people know which plant was edible and which plant wasn't? Were they having a volunteer or was a not-so-fortunate man from the tribe chosen (read: forced) to test the poison level on assorted plants by eating them?