I don't know when they began, Nicola but they were going throughout the 60s. In the late 50s a few South Africans made their way to the top of the game - Sandra Reynolds and Rennee Schuurman made top 10 and Bernice Carr-Vukovich was probably top 20. After these Annette van Zyl was a top player in the mid/ late 60s - she beat BJK to reach the semis at RG one year.
Possibly because there was strength in the home game they grew in stature. Hulett's one of the biggest sugar refineries in South Africa sponsored a couple of the events around 1962 and these were so successful that I think they expanded in 1963 and for a while I think there were 7 or 8 tournaments in total. Whether they were all regarded as the sugar circuit I am not 100% certain but they all followed one another. They were hit by the advent of open tennis in 1968 but I know there were 4 tournaments still taking place in January 1970.
Like Australia they paid a couple of top overseas players to come each year but would not have had the money to subsidise more than a few.
The stars who came in some years were:
1962 Ann Haydon, Christine Truman, Deirdre Catt, Elizabeth Starkie (Annette van Zyl, Sandra Reynolds, Renee Schuurman) - Catt and Sytarkie were two British players in the 60s who at one stage were on the verge of breaking into the world's top 10 but never quite made it.
1963 Maria Bueno, Darlene Hard,(Annette van Zyl, Renee Schuurman)
1964 Maria Bueno, Darlene Hard, Ann Jones, Elizabeth Starkie, Deirdre Catt, (Renee Schuurman, Annette van Zyl)
1965 Christine Truman, Francoise Durr, (Annette van Zyl)
1966 Francoise Durr, Ann Jones, (Annette van Zyl)
1967 Virginia Wade, (Pat Walkden, Annette van Zyl)
1968 Virginia Wade, Carole Graebner (Pat Walkden, Annette van Zyl)
Ann Jones who was looking for "easier" tournaments after 1969 went in 1970 with Peaches Bartkowicz and Pat Walkden competed.
They seemed to have lesser players from 1971 onwards, the results are not listed in the year books.