5. Basil (Ocimum basilicum)
This popular kitchen herb may be more commonly associated with sauce than sorcery, but this hasn't always been the case. Victorian floriography - the practice of assigning codes to flowers to send messages via bouquets and arrangements, also called the language of flowers - associates basil with hatred. This link comes from the ancient Greeks who felt the plant's leaves resembled a basilisk's opening jaws. Maybe you'll pause before sprinkling your friend's pizza with this hateful herb next time…