What is the “John the Conqueroo” made famous by blues singers?

Dear Cecil: Ever since I heard the Willie Dixon tune Hootchie Cootchie Man with the lyrics: I’ve got a black cat’s bone I’ve got a mojo tooth I’ve got a John the Conqueroo I’m gonna mess with you ... I’ve been obsessed with a craving for a John the Conqueroo. Where can I get one? Wesley R., Chicago

Cecil replies:

A “John the Conqueroo,” also known as a “High John de Conquer,” is the root of the St. John’s-wort plant. In southern American black folklore, this root is used to cast or break evil spells–thus all the references to “root rubbing” in blues songs.

Where do you get one? Look around–the St. John’s-wort (Hypericum majus, Hypericum kalimanum, or any of the 23 other Hypericum species) is common to the Northern Hemisphere. Look for an herb with yellow, flesh-colored, or purplish flowers; there are usually five petals on each flower. Hypericum shrubs generally have cylindrical seeds and clustered stamens.

By the way, if someone casts an evil spell on you with a John the Conqueroo, you might be able to counteract the spell with a Jack, a red cloth shaped in a cylinder and filled with dirt, coal dust, and a silver dime.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.