Take a Dive into Watermelons
More than 30 new species of watermelons will debut on the market. Following the trend of “Internet Plus agriculture,” people in Beijing can enjoy the convenience of pickup and delivery services in the same day.
Beijing is entering its hottest season this year. Pedestrians hide themselves in the shade from the burning sun while watermelons in greenhouses enjoy the nourishing sunlight. Farmers take pains to pick the watermelons and move them to cold- chain vehicles but with satisfied smiles on their faces. Consumers may be most joyous to have a feast of watermelons. No wonder a medical poem describes a watermelon as a marvellous
cooler for relieving summer heat.
Beijing's Daxing District will launch more than 30 new species of watermelons. Among them, five were rewarded “New Species Prize” at the 29th National Watermelon and Melon Contest for high quality and excellent taste, including L900, Early-maturing Jiayuan and Baimibao ( White Sweet Melon). Driven by an “Internet Plus agriculture” concept, Beijingers can enjoy a “same- day pickup, same- day delivery” service.
Shitong Melon Park
Panggezhuang Town in Daxing District is as serene as usual in the early morning, filled with the refreshing aroma of watermelons. Farmers have worked for a long time at Shitong Melon Park south of Pang'an Road.
Coming to a greenhouse, we are overtaken by moist and hot air. A fertiliser distribution system comprising of barrels, a pump and delivering pipes at the door indicates that it is a greenhouse applying soil-less culture. Looking around, green and lush watermelons swing through a hanging-vine cultivation technique other than creeping to the ground, looking wellproportioned.
A woman named Yuan Xiaosong owns the melon park. She has worked for nearly an hour although it is just past 7 a.m. She picks a male flower which has just blossomed, exposes its stamen, and carefully applies the stamen to pistils one by one. Yuan says that pollination of each pistil would determine whether a watermelon will have a well-proportioned appearance. In this greenhouse, 2,400 saplings of watermelon are planted. When the temperature in the greenhouse rises to 25 degrees Celsius at around 7:30 a.m. every day, she begins artificial pollination for about an hour. It takes her a week to finish the pollination of all 2,400 saplings. To control the maturing time, she groups the watermelons applied with pollination within two to three days and differentiates them by tying up white, red and purple thin rope. This method is also helpful in the management of water and fertiliser.
In recent years, watermelon growing technology in Beijing's suburbs has improved. People hardly see a watermelon growing on the ground in the open air, instead greenhouses are taking the lead. Soil-less culture techniques help protect watermelons from diseases and increase output, because most diseases arise from soil for plants. A watermelon is even inclined to wilt. If watermelons are repeatedly planted on the same piece of land, all of them would wilt after the third time. Aside from grafting techniques, soil-less culture is the best solution. The technique's base material is composed of sterilised grass carbon and organic fertiliser, reducing the use of insecticides and making it healthier.
The soil-less culture's nutrient elements are mainly supplied by fertiliser distribution. Four barrels respectively labeled A,B, C and D, are filled with four different nutrient solutions, calcium nitrate tetrahydrate in barrel A, ammonium dihydrogen phosphate and sodium silicate in barrel B, potassium sulfate, zinc sulphate, manganese sulphate and ferric sulfate in barrel C, and nitric acid in barrel D. The pump on the barrels extracts solutions at a certain proportion and transmits to another barrel to mix at an appropriate concentration, realising precise fertilisation. Later, the blended nutrient solution is guided by a drip irrigation system to the base material of each watermelon plant. Yuan says that the drip irrigation system requires only 130 cubic metres in a growing season compared with 280 cubic metres for field irrigation.
Yuan is satisfied when she sees the little watermelons growing on green vines. She begins to tie vines ten days after pollination. She says, “It is important to tie the ten-day watermelons up to the vine. Otherwise, their tender peels may be chafed in the wind, resulting in bad appearance. Three to four days after tying vines, watermelon swelling water will be used via a drip irrigation system for 15 minutes for the first time, and again after a week's time. When watermelons become mature about 40 days after pollination, it is best to pick the fruit between 5–7 a.m. for longer preservation time and better taste than those picked at other times.”
It takes about 110 days for a watermelon seed to mature. The fruit can be planted in two seasons in Beijing. The first season can start by the end of January
and harvest in middle and late May. For the second season, watermelon seeds can be planted in early July and reaped before National Day. The application of a hangingvine cultivation and fertiliser distribution system helps increase planting and output, as seen in Yuan's greenhouse which can harvest 2,000 watermelons in a season. This proves greenhouse advantages.
Yuan personally ventilates the greenhouse every morning and closes windows to keep warm each night to guarantee the best growing environment. She also has to conduct water and fertiliser management, pinch branches and trim vines in the muggy greenhouse. With tenhour work every day year-round, Yan has made the Shitong Melon Park into a star field that integrates production, testing, demonstration, promotion and leisure.
Under the sun, rows of delicious watermelons are put in the shade in the courtyard of Shitong Melon Park. Haoyunlai, Tianyu No. 1, Tianyu No. 2, Tianyu No. 3, Meiyu No. 3 and Chaoyue Mengxiang, and various varieties of watermelon are mouth-watering, and staff from Beijing Agricultural Technology Promotion Station evaluate the new species.
The staff carefully test for the peel's hardness, shape, sections, sugar content and feeling in the mouth. Zeng Jianbo, director of Melon Crop Division, praised as the “watermelon expert,” says that they would compare these new species with the publicly recognised Chaoyue Mengxiang, selecting a better one to promote in the market.
The staff scoop some juice from the rim and centre of a cut watermelon, and place it on a sugar meter to test its sugar content. After that, they started to taste and evaluate the watermelons for its pulp and sweet flavour.
The tested ones this time are small watermelons weighing between 1.5–2 kilograms, which have become more popular among Beijingers. Zeng Jianbo introduces that watermelon cultivation in Beijing dates back to the Yuan Dynasty (1271–1368), when watermelons were planted in sandy soil on the alluvial plain of the Yongding River Basin. There are two species of watermelons now planted in Beijing. One is midsized like the Jingxin series, among which Jingxin No. 2 and Huaxin are commonly eaten by Beijing locals and have about 10 degrees of sugar content; and Zaojia series represented by Qilin watermelons which have thin peel and appropriate sugar-acid ratio, taste refreshing, but double the price of common midsized watermelons. Another type is smaller, such as Chaoyue Mengxiang, the L600 and Jingying, with sugar content at 13 and 15, the highest for watermelons. Jingxin watermelons are currently prevalent in Beijing, while its smaller counterparts have rapidly grown. The growing area of small watermelons has exceeded a quarter of the total area for ten years.
The production of small watermelons has improved three times for over ten years. The earliest generation was Hongxiaoyu from Japan. The species tasted crisp with the sugar content at 11.5 at the centre, but it easily cracked. The second was Zaochun Hongyu from China, and bigger than the first with sugar content being 12. In third was the Chaoyue Mengxiang, currently on the market.
For breeding, Zeng says, “The first step of breeding is to introduce a variety of seeds, generally over 20 species at a time considering similar climates, latitude, air humidity and temperature. Then planting the seeds to observe how they grow, and selecting the most appropriate according to indicators. Through selfing (self-fertilising)
and segregation, parent materials in ideal conditions, such as high sugar content, long shape and strong resistance to contagions, will be chosen. Finally, the species catering to the market demands via pairing and matching will be retained. This is a long process that requires a nine-generation breeding process of least three to five years.”
The total output of watermelons in Beijing expects to reach 280 million kilograms this year, far less than one fifth of the total supply in the Beijing market. From the perspective of the coordinated development of Beijing-tianjin-hebei, Beijing will become an innovative display centre of watermelons in the future, featuring tours, watermelon pick-up, and experimental model fields. Watermelons will be planted in Hebei Province, Tianjin and even Shandong Province, and then resold to Beijing.
Watermelons are eaten year-round. In winter, watermelons from Hainan and Yunnan provinces are common, including those from Myanmar and Laos. Most watermelons from Hainan are seedless and have a coarse taste. Watermelons from Weifang and other places in Shandong Province are popular in April and May, where they taste similar to Beijing's with a low sugar content affected by climate. Beijing's watermelons come onto the market in May and June; Jingxin and Chaoyue Mengxiang are high-quality watermelons mainly produced in Daxing District, with some produced in Shunyi and Yanqing districts. In July and August, watermelons from Ningxia Hui Autonomous Region are made available in Beijing, with a sweet and mushy taste, but with thick peel and fibre. In September, large watermelons from Northeast China grown in open fields weigh more than eight kilograms and cater for Beijing's hard, crisp and sweet taste, with 11 degrees of sugar content.
“The National Watermelon and Melon Contests these years prove that Beijing's watermelons are the best, especially the small ones. Among them, the L800 and L900, updated versions of the L600, one of the favourite species in Daxing District, will be promoted at a near equal price but high sugar content and a crisp pulp. Beijing's output of watermelons this year is reduced compared with that of last year, but taste sweeter due to large temperature differences, sufficient sunlight, less rainfall and fewer hazy days,” Zeng says.
Watermelons are more than a fruit. Poems and celebrities eulogised the fruit. In times without air conditioners, cooled watermelons served as fruit air conditioners, so some elderly state that today's watermelons taste less delicious than before.
Accounts indicate that presentday watermelons tasted sweeter than before. In 2012, Zeng regrew Heibengjin, a watermelon species in Beijing in the 1980s and tasted it. He concluded that the species' sugar content was below 8 and had a thick fibre, compared with that above 10 degrees
of Jingxin watermelons. “The watermelon species and techniques of cultivation have improved. Forty percent of a high- quality watermelon is decided by its breeding. Today's watermelons taste sweeter than before,” says Zeng.
Integration with the Internet
How long does it take for watermelons to be transported from field to table? Farmers pick them in the early morning, then wholesalers ship them to the market in the afternoon. The next morning, watermelons are sold to retailers. On the third morning, the watermelons are placed on shelves by retailers, giving customers a selection to pick and choose from.
However, that's in the past. It now only takes up to a day to transport watermelons from the field to the table. Thanks to the rapid development of the Internet, the public can take delicious watermelons within the shortest time. Beijing's watermelon sales modes have become more diverse. Picking watermelons, online sales, wholesale markets, and supermarket sales have developed.
In January 2017, China Internet Network Information Center (CNNIC) completed the 39th version of the China Statistical Report on Internet Development and analysed China's Internet users. By the end of December 2016, the number of Chinese Internet users reached 731 million, an increase of 42.99 million in the year. Internet penetration rate reached 53.2 percent, an increase of 2.9 percent over the last year. The number of Chinese Internet users is expected to reach 772 million in 2017, with gradually improved Internet consumption capacity. With the implementation of “Internet Plus,” the development of Internet-based enterprises has been promoted. By the end of December 2016, the number of China's online shopping users reached 467 million, an increase of 12.9 percent over 2015, accounting for 63.8 percent of Internet users. Among them, the number of mobile phone online shoppers reached 441 million, accounting for 63.4 percent of mobile Internet users. The number of China's online payment users reached 475 million, among whom mobile payment users grew rapidly, reaching 469 million.
The Internet's prosperity has helped open up many sales barriers, speed up circulation, and guarantee quality of goods. Yuan says, “We'll continue to develop our e-commerce as it's the future trend which guarantees benefits. In the meantime, intermediate links have been saved.”
When small watermelons like Chaoyue Mengxiang and L600 were recognised by the market in 2013, Shitong Melon Park began to integrate its business with the Internet. Chaoyue Mengxiang features a high sugar content, crisp taste and tough peel, resistant to storage and transportation. Many e-commerce merchants, including Jingdong, took the initiative to cooperate with Shitong Melon Park and sell Chaoyue Mengxiang on their online platforms. In the past three years, both watermelons sold online and on e-commerce sales platforms have increased. To ensure quality watermelons, staff would pick high-quality watermelons and ship them with anticollision packaging.
“As a small watermelon sales platform, our watermelons are picked in the morning and delivered in the afternoon after careful sorting and packaging, so that customers can enjoy sweet the watermelons the next day,” explains Yuan. In the workshop, Yuan points to 140 boxes of watermelons that have been packaged, saying, “There is great market demand for Chaoyue Mengxiang watermelons. We sold 1,500,000 kilograms of that species last year. These boxes of watermelons have high quality. They have a regular shape, almost equal weight, high sugar content over 12 degrees, pink pulp and fine fibre.
If people want to eat more fresh watermelons, they can go directly to the melon park to pick them by themselves. Zeng says that Beijing's picking agriculture has developed rapidly in recent years. Picking watermelons account for 30 percent of the total watermelon sales volume in Daxing District. Based on market demand, Beijing Agricultural Technology Promotion Station has promoted its hanging-vine cultivation techniques and small-sized watermelons. Last year, it also promoted its apple-sized Jingya watermelon species, providing customers with more choices.
If one thing has to represent summer, the watermelon is it. Though the market has never lacked high- quality watermelons, not everyone has a good command for selecting them. After years of research, Zeng Jianbo, an expert in watermelon, summarises some ways to pick and choose high- quality watermelons.
“It is similar to looking, listening, questioning and feeling in traditional Chinese medicine,” says Zeng. Watermelon peels vary according to species. There is no standard colour that can guarantee a watermelon's quality. Most peels are dark green and light green, but some are yellow, black and even white. Some peels are smooth, while some are covered with a layer of wax. Never judge a watermelon by its external colour.
Take Jingxin No. 2, a popular watermelon species in Beijing, as an example, which features a green peel, clear strips and a layer of frost on its outside. On the other hand, Chaoyue Mengxiang features light colour between strips. As the watermelon matures, dark green or green spots appear on the peel, and become more apparent.
Aside from the peel, the watermelon vine also provides useful information on whether the watermelon is fresh or not. The cross section of the vine is white in the middle and green on its periphery. The riper the watermelon is, the larger the white part of the vine occupies, and the less hair its vine has. In addition, if the connecting part between the watermelon and its vine is concave, the watermelon is more likely to be hollow inside.
Some people believe that fruits with a less beautiful appearance taste good indeed, but Zeng doesn't think so. A smooth peel and round shape have always been evaluation criteria for watermelons. Irregular shape is mainly caused by pollination failure, low temperature and dysplasia. Moreover, insufficient watering might cause the watermelon to taste sweet, but not succulent.
After careful observation, customers might be able to pick out tasty watermelons. If they want to pick out better ones, one skill is necessary— listening. The texture of the pulp varies with the maturity of the watermelon. Pulp texture, moisture content and peel thickness can affect the sonic frequency of a watermelon; sensing the quality of a watermelon by hitting its peel and listing to the echoes inside. As the watermelon matures, the time of its vibration becomes longer, and its vibration attenuation slows down. Zeng says, “Let me put it this way. The vibration frequency declines with the maturity of a watermelon.”
An experiment conducted at Hebei Agricultural University shows that the vibration frequency of immature watermelon is above 189 Hz, that of mature watermelons is between 133 to 189 Hz, and that of overmature watermelons is below 133 Hz. Crisp sounds (high frequency) indicate immature watermelons, while dull sounds (low frequency) indicate mature watermelons.
Zeng also gives consumers some common knowledge on how to pick tasty watermelons. For example, if people claim that their watermelons grow in Beijing's greenhouses in winter, customers should never buy them. It's true that watermelons are available in Beijing throughout the year, but those grown in Beijing are only sold in markets from May to July. Watermelons growing in different places are available at different times. With this common knowledge in mind, the general public can become smarter shoppers of watermelons.
Watermelons tied to differentiate maturing time
Packaging watermelons with anti-collision materials
Testing sugar content
Tapping the watermelon and listening to the inside helps determine its quality.