The ship was originally built as a Flower-class corvette for the Royal Navy during World War II and served as HMS Rockrose (pennant number: K51).

Rockrose was initially assigned to convoy escort duties in the North Atlantic after her completion in 1941 but was later transferred to South African waters and then to the Far East with the same mission.

The ship carried 230 long tons (234 t) of fuel oil that gave her a range of 5,000 nautical miles (9,300 km; 5,800 mi) at 10 knots (19 km/h; 12 mph).

Her bridge was remodelled to improve visibility and a pair of echo sounders were fitted in addition to a navigational radar and direction-finding gear.

The ship was ordered on 21 September 1939 from Charles Hill & Sons[4] and was laid down on 28 October 1940 at its Bristol shipyard as yard number 284.

Gilbert Hamer & Co. of Durban finally began work in mid-1949 and she was recommissioned as HMSAS Protea in February 1950.

She was listed for disposal in March 1961 and was subsequently purchased by Johannesburg businessman Ernest Bisogno, owner of Maritime Fisheries (Pty) Ltd, for R4,000.