 Rupp was made deacon on 28 May 1899 and ordained priest on 2 June 1901.He began recording his botanical observations and specimens in 1892; from 1899 made 'a census of the native plants' of his parishes.In 1924 he decided to 'concentrate on the family which had always attracted me most — the orchids' and gave some 5000 other specimens to the University of Melbourne's botany school.