Plums belong to the genus Prunus, which also includes peaches, cherries, and almonds. Plums are classified as drupes, or stone fruits, characterized by a single large seed encased in a hard shell. Tracing the exact origins of the plum is complicated due to extensive human cultivation, domestication, and natural hybridization across millennia. This has resulted in a wide array of species and cultivars spanning multiple continents and distinct ancestral lines.
The Ancient Origin of European Plums
The Common Plum (Prunus domestica), the most widely recognized species in Western culture, lacks a truly wild native habitat. This species is a hexaploid, possessing six sets of chromosomes, and resulted from an ancient, spontaneous hybridization event. Scientific evidence suggests this natural cross occurred between the diploid Cherry Plum (Prunus cerasifera) and the tetraploid Sloe (Prunus spinosa).
The genetic fusion is believed to have happened in the area encompassing the Caucasus Mountains and the Caspian Sea region, spanning from Eastern Europe into Central Asia, including modern-day Iran. Both parent species are native to this area, making it the cradle of the European plum. The resulting hybrid, P. domestica, became the ancestor of common varieties like prunes, damsons, and greengages. Archaeological findings indicate this fruit was one of the earliest to be domesticated by human populations in this Eurasian corridor.
The Distinct Ancestry of Asian Plums
A major commercial group originated from a separate lineage in East Asia, contrasting with the hybrid origins of the European plum. The Japanese Plum (Prunus salicina) is a significant species in global commerce, but its common name is misleading. Genetic studies confirm this plum is indigenous to China, with its primary domestication center located near the Yangtze River Basin in the southwestern region.
This species was cultivated in China for thousands of years before its introduction to Japan during the Nara period. The fruit is appreciated for its larger size, heart shape, and firm, juicy flesh, making it highly suitable for fresh consumption. Its successful cultivation in Japan led to its popularization and subsequent introduction globally, solidifying the misnomer “Japanese” plum. P. salicina and its numerous cultivars now dominate the modern fresh plum market, providing a clear genetic divide from the P. domestica varieties.
Indigenous Plum Species of the Americas
The Western Hemisphere developed its own distinct plum species, genetically separate from the European and Asian commercial types. These indigenous varieties include the American Plum (Prunus americana) and the Beach Plum (Prunus maritima). P. americana is a hardy, thicket-forming species native to a wide range across North America, extending from the Rocky Mountains eastward.
The fruit of the American Plum was historically used by Native American tribes for food, often processed into jams, preserves, and dried fruit leather. The Beach Plum (P. maritima) is a notable native shrub found along the sandy coastal dunes of the eastern seaboard from New England to Virginia. This species is highly salt-tolerant, and its small, tart fruit is primarily used today in niche markets for specialized jams and jellies. These American species are still used as rootstock for grafting or in breeding programs due to their hardiness and disease resistance.
Global Spread and Modern Production Centers
Cultivated plum species began their global dissemination centuries ago, primarily following trade and military routes. The Romans were instrumental in spreading the European plum (P. domestica) throughout their empire and into Western Europe. Later, European explorers and colonists introduced both P. domestica and the popular Asian plums to the Americas and other temperate regions.
Today, plum production is a global endeavor, with cultivated varieties thriving across six inhabited continents. China, the native home of Prunus salicina, is the world’s largest producer of plums. Major production centers following China include countries in Eastern Europe and the Southern Hemisphere. Serbia and Romania focus largely on European-type plums, while Chile supplies fresh plums to the Northern Hemisphere during its off-season.