Motherwort Herb (Leonurus cardiac) Other names: Lion’s tail, lion’s ear, throw-wort, heartworm, and yi mu cao). Motherwort is a perennial herb and a member of the mint family. It earned the name Motherwort from its continued use by pregnant women in ancient Greece for its calming benefits. The Chinese on the other hand attribute Motherwort to long life. In fact, Chinese legend has it that a youth was banished to a valley where the only water supply was in contact with a large amount of Motherwort plants. Because he drank this daily he lived over 300 years. While this is an obvious exaggeration, it’s another testament to the popularity of this wonderful herb.