He was born on 29 March 1933, in
Råde, to farmers Johan E. Grimstad (1902–1966) and Marie Gammelsrød (1906–1985). He finished basic education in Råde in 1948, then took a year each in
Rygge and
Mysen before attending
Kalnes Agricultural School from 1952 to 1954 and the
Norwegian College of Agriculture from 1958 to 1962. He was briefly a
research assistant here in 1962. From 1962 to 1966, he was a consultant in
Fellesslakteriet, before taking over the family farm in 1966. He spent two years as an aid consultant in
Kenya for two years before finally settling on the family farm in 1968. He was the managing director of Gartnerhallen from 1977 to 1981, then a Nordic aid coordinator in
Mozambique from 1983 to 1987. ==References==