There are about 33 species of Acmadenia, most of them growing in the south-western Cape. They belong to the Rutaceae family. The leaves and fruit of these plants bear tiny oil glands that imbue each species with its own characteristic scent. This reminds of the most well-known genus within the family, viz. Citrus. These species also generally exude strong aromas, especially when the leaves are crushed.
There is an Australian genus of Rutaceae called Boronia that bears fragrant flowers and is used commercially for producing oils (Wikipedia).
Acmadenia mundiana has become a rewarding gardening subject as an ornamental shrub on rockeries and pruned borders. In spite of its natural limestone habitat the plant performs well in average garden soil and circumstances, even as a container plant (www.plantzafrica.com).