Born in Auckland in 1924, Castle started making pottery in 1947, and became a full-time potter in 1963. He is one of the founder of the New Zealand Society of Potters. In 1986, he was made a Commander of the Order of the British Empire for services to pottery. In 1990, he was awarded the New Zealand 1990 Commemoration Medal. Castle was also appointed as a Distinguished Companion of the New Zealand Order of Merit in 2004 for services to pottery. He died in 2011.