Registered as a conscientious objector in World War II, Heron worked as an agricultural labourer in Cambridgeshire before he was signed off for ill health. He returned to Cornwall to work for Bernard Leach at the Leach Pottery, St Ives, in 1944–45. During this time, he met many leading artists of the St Ives School, including Barbara Hepworth and Ben Nicholson. Reacquainted with Cornwall, Heron spent each summer there until it became his permanent home in 1956 after his purchase and refurbishment of "Eagles Nest" the year before from Mark Arnold-Forster, a house Heron had lived in during his childhood. He spent the rest of his life here, until he died at home in March 1999.