Otto Lincke (sometimes Linke, Lindke) appears to have worked at the Salt Pan north of Pretoria (Tswaing Meteorite Crater) in 1875, for in July that year he complained to the authorities that he had no protection there. Towards the end of the year he became the second curator of the botanic garden, established in 1874 at the site of present Burgerspark, Pretoria. He succeeded John H. McLea*, who described him as a thoroughly scientific and practical man. The garden was well established when he took over, for on 5 January 1876 he advertised in the Staats-Courant (Government Gazette) that a variety of trees and bulbs were available for sale.
In December 1876 Lincke requested four weeks leave to collect plants and seeds in the Transvaal, and informed the state secretary that during his absence J.H. van der Hove would stand in for him at the botanic garden. In April the next year the South African Republic was annexed by the British under Sir Theophilus Shepstone. The management committee of the botanic garden, chaired by D.M. Kisch, declared its willingness to serve under the new administration on 30 April, but the response must have been unsatisfactory for on 28 May the whole committee resigned. During these uncertain times Lincke continued to perform his duties. A government proclamation was in force at the time prohibiting the importation of plants, seeds and bulbs, to prevent the introduction of the dreaded Australian Bug into the Transvaal. On 22 May 1877 Lincke requested that the proclamation be changed to allow seeds to be imported from Europe and America, which were still free of the pest. His advice was accepted by the administration and the revised proclamation published in the Staats-Courant on 9 June.
In the Transvaal book almanac and directory for 1877 Lincke advertised the Botanic Garden with the claim that he could supply all sorts of trees and plants suitable for the local climate, as well as agricultural and garden seeds and bulbs, to buyers in the Transvaal and Orange Free State. A new committee, chaired by Lieutenant-Colonel Montgomery and including Dr J. Vacy Lyle* and Samuel Melvill*, was appointed by the British administration in June 1877 to select a more suitable site for a botanic garden. The new garden was established west of the town centre (near present Weskoppies Hospital) and the plants in the old botanic garden moved there. Lincke must have tendered his resignation early in 1878, for in March that year he wrote to Dr Lyle wishing to withdraw his resignation. By December 1879 a new curator, G. Baikie, advertised trees for sale in the Staats-Courant. Meanwhile Lincke had been arrested for some reason, for in July 1878 he demanded compensation for a horse that was lost at the time of his arrest.