Watermelons are a global crop with ancient roots, and more than 1,000 varieties grow throughout the world. The sweet, juicy melon of summer is a welcome part of meals everywhere, but in Japan, watermelons are both a best-selling fruit and a status symbol!
A Brief History of Watermelon
Watermelon’s ancestors originated on the African continent. But these wild melons were white fleshed, bitter, and pithy – nothing like the sugary fruit we crave today. Recent genetic research on watermelons indicates their domestication began in West and northeast Africa. Based on DNA sequencing of wild and domesticated melons, researchers isolated the Kordofan melon from Sudan, a sweet, white-fleshed melon still grown today, as the closest living relative of the modern watermelon. However, researchers at Kew Royal Botanic Gardens conducted genetic sequencing of 6,000-year-old watermelon seeds found in an archaeological site in Libya that complicates the story.
Egyptian tomb paintings suggest that sweet-fleshed watermelons were growing in the Nile Valley more than 4,000 years ago, and they soon spread to other ancient cultures, including Greek, Persian and Roman – and eventually to China via the Silk Road trade routes established during the Han Dynasty (130 BCE to 1453 CE). In the early 1970s, the well-preserved, 2,000-year-old body of Xin Zhui, a Chinese noblewoman also known as “Lady Dai,” was discovered in Hunan Province. Pathologists concluded that her last meal included both melon and melon seeds.
It is hard to know when watermelons made their way to Japan, but given the many influential cultural and political exchanges between the Tang Dynasty and the Japanese Heian court, it is easy to imagine that melons were introduced to the Japanese archipelago sometime during the era in the 8th and 9th centuries when these governments overlapped. Both the Chinese and the Japanese characters for watermelon ”西瓜”translate to, ”Melon or gourd from the West,” making it clear that watermelons spread from west to east.
There are some clues as to the timing of watermelon’s arrival in Japan. In his Choju-Giga pictographic scrolls of frolicking animals and humans (sometimes referred to as the first “Manga,” or comic book), artist and Buddhist monk Toba Sojo depicted a rabbit presenting a fruit tray to a monkey priest. Striped watermelons are clearly visible among the fruits. The scrolls belong to Kosanji Temple in Kyoto.
Portuguese traders also brought pumpkin and watermelon seeds to Nagasaki in 1579, the 7th year of Tensom (Momoyama period). Japan’s era of trade with the Portuguese began in 1543 when a Portuguese ship blew off course and landed on the tiny island of Tanegashima. The Japanese called them “Nanban,” or “southern barbarians,” since they were sailing from the south.
A seedling introduction project from Russia at the end of the Meiji era (1868-1912) helped advance watermelon cultivation in Japan. Watermelon breeding projects with China and the U.S. followed in the Taisho era (1912-1926), helping to bolster the bio-integrity of native Japanese watermelon varieties.
Watermelons, Japanese Style
Today you’ll find more than 20 popular watermelon types on the Japanese market, including Benidai, Fujimitsu, Striped King, and Matsuribayashi 777. Recently, the demand for Kodama watermelon has increased dramatically.
One of our favorite Japanese varieties is Silver Yamato, bred by Takeshi Kanda, a renowned watermelon expert of the early 20th century. The light-fleshed melon from Nara Prefecture has a sweet and complex flavor that wins rave reviews.
Japanese watermelons tend to have firm, juicy flesh, and a delightful mouthfeel, perhaps because of the attention breeders and growers pay to create the perfect gustatory experience on a hot summer’s day!
Of course, Japan is also famous for producing watermelons in unusual shapes, such as cubes, hearts, and pyramids, as high-end gifts that fetch astonishing prices. These melons are picked green (and thus are inedible) and can be stored for months.
The trend started around 1970, when the price for melons plummeted due to intense market competition from sweets like juices and ice cream. A group of farmers from Zentsuji, Kagawa Prefecture, came together to brainstorm ways to create renewed interest in their melons. Someone suggested in jest that they should change their shape.
One of the growers, Takashi Yamashita, wholeheartedly embraced the idea, experimenting with a cube-shaped mold for the melons. At first his goal was to make it easier to store watermelon in a small Japanese refrigerator. But the cost of cultivating and shipping the fruit was too much for most people, so the farmers of Zentsuji turned to growing
ornamental square melons instead. Takashi Yamashita died in 2016 at age 93, but his son Toshiyuki Yamashita has continued the tradition of the “Shikaku watermelon.” He is the chairman of the Zentsuji Watermelon Subcommittee, an affiliate of the Ministry of Agriculture, Forestry, and Fisheries.
Today, just a handful of growers like Toshiyuki Yamashita are responsible for the painstaking cultivation of these novelty melons. Farmers select fruit of a certain size from their fields and carefully place the fruit in a glass and metal box. Each fruit grows inside the patented mold for about two weeks – and not all of them will make the cut!
Japanese agricultural law protects Zentsuji as the designated growing area of the square watermelon. The Geographical Indications, or GI, status protects the name of agricultural products as intellectual property whose “quality, reputation and other established characteristics are essentially attributable to its geographic origin.”
Only a few hundred cube watermelons are sent to market each year, and each fruit gets a sticker of authenticity before it is packed into a perfectly sized square box for shipping.
These are luxurious gifts for the ochugen, or mid-year gift-giving season, which runs from early July to mid-August, depending on where you are in Japan. These midsummer gifts are a way of expressing gratitude or showing love or respect. Often, these spendy, shaped watermelons are given as corporate gifts.
Molded watermelons are not the only big-ticket melons in Japan, though. The Densuke watermelon, a black-rinded variety grown only on the northern island of Hokkaido, sometimes sells for up to $6,000 apiece! Fewer than 100 of these sweet, crunchy, red-fleshed, and nearly seedless melons are sold each year.
The Densuke is not a melon for playing suikawari, a pinata-like game in which blindfolded players swing at a watermelon with sticks until it breaks. Luckily for players of this popular summer beach game, there are plenty of other amazing Japanese watermelons from which to choose!
Key Takeaways
- Watermelon originated on the African continent, but it was nothing like the sugary sweet fruit we enjoy today.
- Based on DNA sequencing of wild and domesticated melons, researchers isolated the Kordofan melon from Sudan, a sweet, white-fleshed melon still grown today, as the closest living relative of the modern watermelon.
- Though it is not known exactly when watermelons arrived in Japan, it could have been as early as the 8th or 9th centuries, given the many cultural exchanges between Japan and China at the time.
- Today there are more than 20 Japanese watermelon types on the market.
- Watermelons grown in molds are expensive gifts for special occasions, and very high-end melons such as Densuke are highly prized. A single Densuke can cost $6,000!
About the Authors
Michelle Johnson is a nationally award-winning writer and editor. Her favorite job at Baker Creek is as the unofficial seed historian. Mark Wideman of Baker Creek's Japan team contributed research to this story.
