 Cardew was also an accomplished pianist and played the trumpet with St Breward Silver Band.Seth's second marriage was to the quilt maker Roberta Pejic and they relocated to Masia Albadas, Spain, in 2005.He died in the United States on 2 February 2016,

Cardew’s work is exhibited in Birmingham City Art Gallery, the Royal Cornwall Museum, Truro, the V&A and the William Alfred Ismay collection at the York City Art Gallery.