A Brainbloom was a result bio-organic grafting of plant and human in the 21st century. They grew like flowers but could imitate any known sound. Dredd's lanlady Maria did not know that possession of a brainbloom was a crime under the Bio-Penal Code because of 'what they were fed on'. Ma 'Green Fingers' Mahaffy taught her brainblooms the hypnotic Humming Song.