Merilyn was born in Auckland in 1941. She completed a Preliminary Diploma at the Elam School of Art in 1959 and continued her studies at Goldsmiths School of Art, University of London, graduating in 1963 with the National Diploma of Design, and in 1964 with the Art Specialist Teachers Diploma. However, while on a working holiday in a small country pottery in Ireland, she became more and more interested in working with clay. Merilyn said "I'd spent three years at Goldsmiths specializing in painting....and then I watched someone throwing pots on a wheel ..amorphous lumps of clay, two hands, a little water, and a slowly turning wheel....It was like watching a dance in slow motion....I was hooked"

Merilyn returned to New Zealand and in 1976 built a two chambered wood kiln at her home near Albany. She has worked as a professional ceramicist since that date. She was selected to participate in the National ceramic symposium held in Dunedin in 1989, and in the First International Ceramics Symposium at the Canberra School of Art in 1989. She has received several QE11 Arts Council grants, and her work has been recognised with many awards, including the Fletcher Challenge Pottery Award, and the Premiere Portage Ceramic Award in 2005 for Arctic Rim. In 2002 Merilyn's Pacific Rim, a white earthenware clay piece, was featured on a special edition of stamps issued by New Zealand Post and Sweden Post called ‘Art Meets Craft.'

Merilyn received an Arts Foundation Laureate Award in 2007. The Award money went toward the development of a new studio space in Auckland.

Merilyn's works are held in many national collections. She gradually moved away from the Anglo Oriental influenced style that dominated ceramics early in the contemporary craft movement in New Zealand, developing her own personal approach which has come to demonstrate a strong sense of place.

Merilyn Wiseman died 13 June 2019