The Sakurajima Radish is known as the “Largest Radish in the World.” It has produced radishes at a standard weight of 13 pounds and is capable of reaching 100 pounds! This traditional variety of daikon radish has a round basketball-like shape, unlike its longer and skinnier daikon relatives. Daikon radishes were introduced to Japan over 1,300 years ago, and there are over 120 varieties with unique characteristics cultivated regionally. During the Edo Period (1603-1868), daikons became extremely popular, and today 90% of daikons are produced and consumed in Japan. However, the regional varieties have slowly been replaced by the F1 hybrid variety called Aokubi. Aokubi and other F1 hybrids now account for the majority of the daikon production.
The Sakurajima Radish represents one of the few regionally cultivated varieties of daikon still being grown in Japan. Named after its place of cultivation, the former island of Sakurajima in Japan's Kagoshima Prefecture, the radish is thought to have been grown since at least 1804 and most likely before this date. Sakurajima was the southern most island in the Kagoshima Prefecture with volcanic soils where rice would not thrive. In place of rice, the mammoth white radish was grown in mass amounts as a commercial crop and hauled to Kagoshima City to trade for straw. At the height of its production, as much as 500 acres would be planted each year.
Although the region has a long history of volcanic activity that began to impact the production of this magnificent radish. Sakurajima is a composite of mountains with three peaks that express volcanic activity. The first recorded volcanic eruption occurred in 963 A.D. Smaller eruptions occur constantly. Sometimes 1,000 eruptions can occur in a year, although larger eruptions have been recorded in the 1400s, 1700s and more recently in 1914.
1914 volcanic eruption at Sakurajima in Kyushu, Japan
The 1914 eruption instigated lava flows that lasted for months. The lava connected Sakurajima Island to the Osumi Penninsula by a thin isthmus, attaching it to the main land and taking away its island status. The enormity of the 1914 eruption significantly decreased the land available to grow the staple crop. Since 1955, ash has been dropping consistently and has created challenging growing conditions. As a result, the growing area was decreased to as little as 3.5 acres by 2001. In August of 2015, the Japanese Meteorological Agency gave the volcano a Level 3 (Orange Alert), warning people that the volcano is active and should not be approached.
As a traditional crop, it continues to have a key role in Japanese cuisine. Sakurajima Radish can be pickled in a salt brine and used as a tsukemono, or “pickled things.” The large radish is known for having a sweeter and firmer flesh than other daikon varieties. It also stores well in potato-like storage conditions. Therefore, it is well suited for simmering and for being used in soups, as it will keep its structure and firm texture. While the Sakurajima Radish is no longer a key commercial crop of the region, it remains a beloved traditional crop. Recently the growing area has begun to expand again for its production.