Ken Watson began curling at the age of fifteen as a student at St. John's Technical High School. He entered his first Manitoba Bonspiel in 1923 and won his first trophy in 1926 at twenty-one years of age. Watson led his Strathcona rinks to Manitoba Championships in 1936, 1942, 1943, and 1949. In addition, Watson's team won national honours and the coveted Brier Trophy in 1936, 1942, and 1949. Under his leadership, Watson's teams were Grand Aggregate Champions in the Manitoba Bonspiel in 1939 as well as the six-year period from 1942-1947. In total, his teams have won thirty-two trophies in Manitoba Bonspiel competition.

In 1939, Watson founded and organized the first Provincial High School Bonspiel in Manitoba. He was instrumental in the organization of a national curling school as well as promoting world curling in association with the Scotch Whiskey company, which was the forerunner of the Air Canada Silver Broom competition.

As an administrator and volunteer, Watson served as Chairman of the Manitoba Curling Association Junior Committee, President of the Strathcona Curling Club, President of the Manitoba Curling Association, and Chairman of the Dominion Junior Curling Association Committee. Watson wrote extensively on curling for many newspapers across the country and was the author of several instructional books on curling technique.

Watson was inducted to the Canadian Sports Hall of Fame in 1969 and received the Order of Canada on June 25, 1975.