[5] The family moved to Linköping in the Swedish province of Östergötland in 1953, were both Jöhncke and his brother Johan learned golf and both advanced to elite level in the country.

Four years after coming to Linköping Golf Club, Jönhcke reached handicap scratch and quit ice hockey and other sports he had practiced in his youth.

For the 1968 Eisenhower Trophy in Melbourne, Australia, during the peak in Jöhncke's amateur career, the Swedish Golf Federation decided to not send a team.

However, Jöhncke in 1968 was appointed, for the third of six appearances, to the Continent of Europe team to meet Great Britain and Ireland for the St Andrews Trophy.

In 1968, at the first visit in Sweden by Arnold Palmer, Jöhncke, recognized as the best amateur player in the country, was invited for an exhibition match over 18 holes at Falsterbo Golf Club with Palmer, Sven Tumba and the best Swedish club pro at the time, John Cockin, drawing approximately 5,000 spectators.

[14] Jöhncke was married to Madeleine Nessim, deceased in 2003 at 58 years of age,[15] whose sister, Mona, was married to famous Swedish sports man, ice hockey player and golf entrepreneur, Sven Tumba, with whom Jöhncke was team mate, representing Sweden, at the 1970 Eisenhower Trophy in Madrid, Spain.

Six years later he quit his bank job and started his own business, to later become a real estate developer and moved to North Palm Beach, Florida.