Prune vs. Plum: What’s the Difference?
As I wrote in this article, Sumomo (スモモ) is a Japanese plum that becomes sweet when ripened, unlike Ume (梅), also known as the Japanese apricot.
Sumomo has another name Plum (プラム), and in Japan, there is also a fruit called Prune (プルーン), which is similar to a Plum.
Prune vs. Plum in Japan
To get to the point, while the original home of Sumomo is China, and Plum is also known as Toyo Sumomo (東洋スモモ: meaning Oriental Sumomo),
Prune is native to Europe, also called Seiyo Sumomo (西洋スモモ: Western Sumomo).
The present Plum sold in the market is what came back to Japan after selective breeding in the United States in the 19th century.
Now, Plum is available in various varieties, and representatives include 大石早生 (Oishi Wase), ソルダム (Soldam), and 太陽 (Taiyo).
While Plum is from Prunus salicina or the Chinese/Japanese plum, Prune is from Prunus domestica or the European plum.
The best season for Prune is almost the same as Plum, spanning from mid-July to September, and popular varieties include サンプルーン (Sun Prune), シュガー (Sugar), and スタンレー (Stanley).