Most of the commonly grown plum cultivars grown in South Africa require a cross-pollinator to effectively set fruit. In recent years, a better understanding of the biochemical mechanisms involved have led to the development of technologies that enable the determination of compatible cross pollinators on a molecular level.
The accompanying table has arranged a large number of plum cultivars grown in South Africa, roughly according to flowering window with a coloured indicator of genetic relationship, either genetically compatible (green box), incompatible (red box), or untested (grey box) as well as the most commonly recommended pollinators (blue and purple boxes).
* Molecular data provided by 
It is important to note that this is information cannot be interpreted in isolation, and determining whether the cultivar and cross pollinator combination overlaps in flowering time remains the responsibility of the producer or technical consultant involved in the design of a new orchard.
For more information or to have your cultivars tested, contact Carl Hörstmann, carl@provar.co.za