Cultivating the world's largest citrus fruit
Originating in Southeast Asia, the Banpeiyu is said to be the largest citrus fruit in the world.With pale yellow skin, large specimens have a diameter of about 25 cm. There are some that weigh more than 2 kg.Leaving them out for about a month after picking until they are ready to eat allows you to enjoy a refreshing citrus fragrance.Stock was introduced to Japan in earnest in 1930, and cultivation began in Yatsushiro, Kumamoto prefecture.Kumamoto is a major production area that accounts for over 90% of the Japanese Banpeiyu harvest.That evening I visited Junichi Nishida, a citrus farmer who grows Banpeiyus without using pesticides or fertilizers.
The Banpeiyu is a variety of citrus maximus. The Japanese name, “banpeiyu,” is said to be derived from the fact that the flesh of this citrus fruit is white (“peiyu”), and that it is a late-growing crop (“ban” means late). It is the world’s largest variety of citrus fruit. In 1920, Yaichi Shimada, a botanical researcher in Kumamoto prefecture, brought samples back from Vietnam and tried to cultivate them. Although they didn’t spread at the time, in 1930 stocks from Taiwan were introduced in earnest, and cultivation began in Yatsushiro, Kumamoto prefecture. Currently, Banpeiyus are known as a specialty of Yatsushiro, and vigorous cultivation is carried out here. The thick skin is a pale yellow, and there is a cotton-like white layer called albedo inside that dresses the flesh. Because of its long shelf life, it can be used as a decoration indoors for about a month after harvest, during which time the fruit has a distinctive refreshing fragrance. When a large section is held in the mouth, a mild acidity spreads, with a clean aftertaste. In Yatsushiro, not only the flesh, but also the skin and albedo, cut into short sticks and preserved in sugar and pickled, which is Banpeiyu -zuke, is known as another specialty of the area.
Junichi Nishida, the representative producer of Nishida Orchards in Tamana district, Kumamoto prefecture, is a rare farmer who cultivates citrus fruits without the use of pesticides. “It’s sort of a fusion of Steiner’s biodynamic agriculture method, with its mowing, pruning and harvesting according to the phase of the moon, and natural cultivation,” says Nishida of his original farming method. In addition to Banpeiyus, he grows about 30 varieties of citrus fruits including Satsuma mandarins, shiranui, hassaku oranges, hyuganatsu, and lemons.
“Minerals hold the key as to whether a citrus fruit will grow to be delicious,” said Nishida-san as he guided me up the steep mountain slope. “Because the soil here is red clay mixed with limestone, it is rich in minerals like potassium and calcium. An environment perfect for growing delicious citrus.”
The Banpeiyu trees, which were planted by his father’s generation in the orchards founded by his grandfather, are about 40 years old. In order to prevent scratches by the twigs and branches and such before harvest, they were planted in places suitable for growth and not easily affected by typhoons, each one planted individually here and there along the slope of the mountain. “One tree yields about 30 fruits. They’re very big fruits, so before harvest the limbs bend and warp quite a lot. When allowed to ripen the sweetness turns into a delicious umami, so after harvesting I let them ripen in a storehouse with a maintained temperature of about 5°C,” says Nishida.
Cultivation in a natural environment without the use of pesticides, fertilizer, or even a hothouse also affects the appearance of citrus fruits. Apparently, there are often black spots and scratches on the skin due to the rain and wind. In general, the Banpeiyus you see on the market have smooth skin, but “scratches are proof that natural cultivation was used and that no pesticides were used,” Nishida-san explains in a clear tone.
In addition, Nishida-san carefully considers the cycle in which trees bear fruit, and doesn’t perform fruit thinning to regulate the number of harvests. “With fruit thinning, the physiology of the tree becomes disordered. Without doing anything, they will reliably produce fruit every two years,” he says. “In years when the trees produce a lot, the fruits are delicious because they have an instinct to compete with each other in flavor. They can be enjoyed just once every two years, but I have to go along with the trees’ natural instincts.” “It is for those who understand this sentiment that I want to deliver these fruits,” he adds.
After graduating from university, Nishida-san had experience working for a major electronics manufacturer. While involved in work with the company’s environmental department, he began to feel contradictions, and came to think about environmental issues. “I began to feel that I wanted to do something more natural and organic,” he says.
After inheriting the orchard, he increased the varieties being cultivated as he reviewed the topography and soil of the mountain, and began to perform multi-variety cultivation. In addition, he adopted a cultivation method that doesn’t use any petroleum products such as vinyl, and doesn’t require the use of any fuel that is needed with hothouse cultivation. Nishida-san, who talks about cherishing the “story” of citrus fruits before eating them, is developing a series of fruit bearing the name “Tsuki Yomi” (Moon-Reading), which expresses the spirit of his cultivation method. He relates that from now on he wants to continue using his original method of farming that is a fusion of natural cultivation standards and protect the value of suitable crops in suitable locations, and continue to consider the diversity of trees and grasses in the area to grow delicious citrus fruit. As I listened to these words, Nishida-san gave me a Banpeiyu. It was profoundly heavy, and reminded me of the natural forces at work in the orchard.
At Nishida Orchard, fruit is cultivated in accordance with the rhythm of nature, and as a general rule harvested fruit is sold directly. Nishida-san also puts efforts into processing, and sells items such as juices that are pressed with the skin intact. From the left, blood orange (1 ℓ, 2,300 yen/tax not included), Satsuma mandarin (1 ℓ, 2 000 yen/tax not included)
671-3 Harakura, Gyokutomachi, Tamana district, Kumamoto Prefecture