Two of Penny Harris' forebears were well-known artists. Her great-grandfather, Washington Francis Friend, was a Canadian watercolourist. Her mother, Olive Frances Friend, was a painter in the pre-Raphaelite style. Penny Harris was initially taught by her mother, going on to study at Exeter College of Art. She painted along traditional lines until she discovered the art of painting on glass and developed a career as a painter of wildlife in this medium. She signed her work 'Matrix'.

During the 1980s she acquired an unusual gallery for her paintings, in the 11th century South Gateway leading into the town of Launceston in east Cornwall.