Kaifeng Watermelon

Kaifeng Watermelon

Kaifeng watermelon is a product with geographical indication.

　　The Kaifeng watermelon plant grows vigorously, sprawling along the ground with thick vines and large leaves. The main vine can exceed 2 meters in length, with strong branching ability—producing numerous lateral or sub-vines, which in turn sprout tertiary vines. The internodes are about 10 cm long and around 8 mm in diameter. The functional leaves are palmately deeply lobed, with 59–67 green leaves during the fruit-swelling stage. The root system consists of a taproot, multi-level lateral roots, adventitious roots, and numerous root hairs. The taproot can penetrate the soil to a depth of 1.5 meters, with a lateral spread of 1.5–2 meters. The fruit rind comes in various colors, including black, green, striped, and yellow, while the shapes include oval, round, and elongated oval. The fruits are uniform in size, with a bright and clear surface. The flesh is consistently bright red or yellow, with a moderately firm yet tender texture, fragrant and refreshing, free from off-flavors, juicy with few or no seeds, lacking coarse fibers, and offering a well-balanced sweetness. It stores and transports well. The variety exhibits strong stress resistance, vigorous growth, with an average yield of 2,860 kg per mu, reaching up to 3,500 kg at its highest. In summary, Kaifeng watermelons are beautifully shaped, brightly colored, fragrant, refreshing, and of exceptional quality.

　　Geographic Scope

　　The protected area for the Kaifeng watermelon geographical indication spans nearly 50 townships (towns) across five counties and two districts of the city, with key distributions in townships such as Xijiangzhai, Fancun, Zhuxianzhen, Banpodian, Wanlong, Yuanfang, Chou Lou, Chenliu, and Xinglong in Kaifeng County; Didie, Dagangli, Lizhuang, Yuhuangmiao, Sisuolou, Zhusha, Shugang, Changzhi, and Chengguan in Tongxu County; Shuipo, Zhangshi, Zhuangtou, Yongxing, Xingzhuang, Shibal, Daying, Menlouren, Xiaochen, Gangli, and Weichuan in Weishi County; Yifeng, Putaojia, Guyang, Guying, Zhangjunmu, Chengguan, Zhuaoying, and Nanzhang in Lankao County; Chengjiao, Shiyuan, Gaoyang, Gegang, Yangju, Pingcheng, Shawo, and Xingkou in Qixian County; Xinghuaying Township, Xijiao, and Shuimiang Township in Jinming District; and Xianrenzhuang and Nanjiao Township in Gulou District. The total protected production area covers 267,800 hectares, with an actual cultivation area of 40,000 hectares and an annual output of nearly 1.8 million tons. Kaifeng City, Henan Province, is located between 113°52′–115°02′ east longitude and 34°12′–35°01′ north latitude, situated in the eastern-central part of Henan, at the tip of the Yellow River alluvial plain. It borders the Yellow River to the north, the Huang-Huai Plain to the south, eastern provinces to the east, and lies 72 km west of the provincial capital, Zhengzhou. It occupies the central position of the eastern Henan Plain, with an urban area of 362 square kilometers, stretching 92 km from north to south and approximately 126 km from east to west.

　　Natural Ecological Environment and Humanistic Historical Factors

　　(1) Soil and Topography: Kaifeng is located in the southwestern part of the massive alluvial fan formed by the Yellow River as it flows eastward from Ningzuixia in Mengjin County, forming part of the alluvial plain jointly shaped by the Yellow and Huai Rivers. The terrain is higher in the northwest and lower in the southeast, with a slope of 1/1000–1/2000, and is generally flat. The sediments that make up the plain are primarily...

　　alluvial deposits mixed with aeolian accumulations. Frequent breaches and course changes of the Yellow River have created numerous alluvial and aeolian sandlands, sand dunes, sandy mounds, inter-dune depressions, and beach areas. The city’s soils are categorized into four major types, three subtypes, six soil genera, and 42 soil species: fluvo-aquic soils, saline soils, aeolian sandy soils, and recently deposited soils. The general soil distribution is sandy in the west, alkaline in the north, and loamy (loamy fluvo-aquic soils) in the central and southern regions, with some clayey (clayey fluvo-aquic soils) areas in local depressions. The terrain is flat, the ecological environment is favorable, land resources are abundant, soil fertility is high, with an average soil pH of 7.5–8.5, organic matter content of 1%, total nitrogen of 0.09 mg/kg, available phosphorus of 10 mg/kg, and available potassium of 80 mg/kg. The soil is fertile, loose, and highly suitable for the growth of Kaifeng watermelons.

　　(2) Hydrology: The city’s rivers belong to the Yellow River and Huai River systems, with tributaries including the Wohe, Huiji, Jialu, and Hongwei river systems in Kaifeng. The water source is groundwater, with irrigation mainly relying on well irrigation. The irrigation water quality for crop farming meets the corresponding standards for pollution-free food, ensuring water quality compliance and suitability for producing pollution-free agricultural products.

　　(3) Climate: Kaifeng is located in the northern warm temperate zone. In winter, it is influenced by polar continental cold air masses, while in summer, it is affected by warm air currents from the Pacific and Bay of Bengal. The four seasons are distinct, characterized by “dry and windy springs, hot and rainy summers, cool and sunny autumns, and cold winters with little snow or rain,” representing a typical monsoonal continental climate. Temperature: The long-term average temperature is 13.24°C, with January averaging -0.5°C and July averaging 27.1°C. The annual average temperature is 14.24°C, with extreme highs of 42.9°C and lows of -16°C. Humidity: Absolute humidity is 1.98 mm, relative humidity is 79%. Sunshine: The annual average sunshine duration is 2,267.6 hours, with a sunshine rate of 51%, and an average frost-free period of 213–215 days. Precipitation: The average annual rainfall is 670 mm, with a maximum of 260 mm. January sees 7.5 mm of rainfall, while July receives 156.5 mm. Evaporation: The long-term average annual evaporation is 1,925.3 mm, with January averaging 62.1 mm and June averaging 331.5 mm. The maximum depth of frozen soil is 29 cm, maximum snow accumulation is 35 mm, with a maximum snow pressure of 20 kg/m². The average number of sandstorm days is 9.3, and thunderstorm days is 23. Wind direction frequencies are: NGN 12.75%, N 12.04%, SSW/S 9.97%, C 100.85%, with an average wind speed of 4.5 cm/s and wind pressure of 35 kg/m². Accumulated temperature: Above 0°C averages 5,162.5°C, totaling 305 days annually; above 5°C averages 4,972.6°C, totaling 255 days; above 10°C averages 4,611.2°C, totaling 215 days; above 15°C averages 3,942.5°C, totaling 167 days. These accumulated temperatures fully support double-cropping of local crops annually and meet the temperature requirements for the growth period of heat-loving Kaifeng watermelons.

　　(4) Humanistic History: Kaifeng is one of China’s three major watermelon-producing regions, with a watermelon cultivation history spanning over a thousand years.

　　Planting began during the Five Dynasties period, flourished in the Song Dynasty, and has continued for more than 1,000 years. Fan Chengda, a poet of the Southern Song Dynasty, wrote in his poem “Watermelon Garden”: “Green vines lie on soft sand against the frost, and watermelons are eaten everywhere these years.” The famous Song Dynasty painter Zhang Zeduan’s “Along the River During the Qingming Festival” also depicts three scenes of watermelon vendors, illustrating the widespread cultivation around the capital—Kaifeng—at the time. Over the years, through careful cultivation and selective breeding by the people of Kaifeng, the Kaifeng watermelon has become a renowned and high-quality product both within and outside the province. Production levels have steadily improved, with cultivation area expanding from 38,000 mu in 1980 to over 600,000 mu today, and yields rising from 1,500 kg to nearly 3,000 kg per mu. Product quality has also significantly improved, with research capabilities and varietal resource advantages leading nationally. In 1991, Kaifeng was named a “National High-Quality Watermelon Seed Breeding Base” by the Ministry of Agriculture, and in 1992, Kaifeng watermelons were awarded the title of “Henan Provincial Famous Brand Agricultural Product.” In national watermelon competitions over the years, Kaifeng watermelons have won multiple awards. Their excellent quality has led to over one-third of the produce being exported annually to more than 20 provinces, cities, and regions across the country, including Hunan, Jiangsu, Guangdong, Zhejiang, Anhui, Shanghai, and Hong Kong. Sales to Hong Kong alone exceed 600 tons during peak season each year, accounting for 8% of the Hong Kong market share. The city has a large number of domestic and international merchants, forming a relatively stable watermelon purchasing and sales network.

　　Production Technical Requirements

　　(1) Origin Selection and Special Provisions: Kaifeng watermelons are grown in areas away from industrial parks in cities and counties, free from various industrial pollutants, with a sound ecological environment, fresh air, fertile soil, even precipitation, and ample sunlight—providing ideal ecological conditions for watermelon growth. The region has good drainage and irrigation facilities, superior varieties, standardized production techniques, and farmers who follow pollution-free watermelon production protocols.

　　(2) Variety Selection and Specific Requirements: Varieties are selected based on market demand, with criteria of high quality, high yield, and strong stress resistance. A rational layout of early, mid, and late-maturing varieties is maintained. Early- to mid-season varieties mainly include Tianbao, Banzhaolu, Kaiza No. 2, Jingxin series, Zhengkang series, and some gift watermelons. Late-season varieties primarily consist of seedless series like Cuibao No. 5, Heimi series, Taiwan Xin No. 1, and Kaiza series.

　　(3) Production Process Management: Kaifeng watermelon production follows pollution-free watermelon production technical protocols. It is recommended to choose higher ground with convenient drainage and irrigation, deep soil layers, loose and fertile sandy loam or loamy soil, avoiding continuous cropping. For agricultural inputs, fertilizers should primarily be organic, with controlled use of chemical fertilizers and balanced fertilization practices. For pest and disease control, integrated management is advocated, prioritizing agricultural and physical methods, supplemented by chemical measures. Chemical control emphasizes bio-pesticides, selecting highly effective, low-toxicity, and low-residue compound pesticides.

　　Key cultivation techniques include: A. Seedling raising: Using small arch sheds with ground cover films for protected cultivation, grafting onto Super F1 or local pumpkin rootstocks. Transplanting occurs when temperatures stabilize above 10°C and ground temperatures at 10 cm depth in the shed reach above 13°C. Transplants are watered sufficiently at planting. B. Pruning: Using a two- or three-vine system, retaining only the main vine and two lateral vines, fixed with branches to guide directional growth. C. Fruit management: Selecting the second and third female flowers on the main vine for fruit setting, with manual assisted pollination. D. Fertilization and irrigation: Balanced fertilization is practiced, with emphasis on base fertilization using well-rotted high-quality manure and soybean meal (3,000–4,000 kg/mu), supplemented with 50–60 kg/mu of compound fertilizer. Topdressing focuses on quick-acting phosphorus and potassium fertilizers, including 5 kg/mu of nitrogen fertilizer for seedling promotion, 20 kg/mu of potassium sulfate compound fertilizer during vine extension with one watering session, and 30 kg/mu of potassium sulfate compound fertilizer during fruit swelling. Watering is adjusted according to weather after each fertilization, typically 3–5 times during the growth period, stopping 5–7 days before harvest. E. Integrated pest and disease management: Advocates agricultural, physical, and biological measures, strictly prohibiting high-toxicity pesticides, rotating efficient, low-toxicity, and regulated pesticide varieties, and strictly adhering to safety interval regulations.

　　(4) Product Harvesting and Post-Harvest Processing: Watermelons are harvested at the appropriate time when they exhibit the inherent characteristics of their variety. Unripe melons are not allowed on the market. Generally, seeded watermelons are harvested 28–33 days after pollination, and seedless ones 35–40 days after. Sampling inspections for pesticide/fertilizer residues and sugar content are conducted before harvesting. Grading and packaging are done based on fruit appearance, with temporary storage in cool, dry, and ventilated areas if needed.

　　(5) Production Record Requirements: Accurately record production inputs, especially the names, sources, usage methods, dosages, and application/cessation dates of fertilizers and pesticides; the growth and harvest periods of watermelon fruits; quality inspection details; and sales information.

　　Typical Quality Characteristics and Product Quality Safety Standards

　　for repeated detailed description of plant growth, fruit characteristics, and quality attributes.]

　　(2) Internal Quality: [See

　　(3) Safety Requirements: Kaifeng watermelons strictly adhere to national mandatory technical standards during production, including GB4285 for pesticide safety use, GB13/453-2001 for pollution-free vegetable pesticide use guidelines, GB16175.1-1996 for melon and vegetable crop seeds, NY/T496-2002 for fertilizer rational use and testing, and NY5110-2002 for pollution-free food vegetable growing environment conditions.

　　Packaging, Labeling, and Related Regulations

　　Kaifeng watermelons of the same variety, regular shape, and consistent size are considered qualified. Smaller, misshapen, or damaged fruits are handled separately. Watermelons certified as pollution-free must be packaged for sale. Packaging materials must comply with national mandatory standards. Before packaging, each watermelon is bagged, then placed in packaging bags or boxes. Users of the “Kaifeng Watermelon” label must uniformly display the “Kaifeng Watermelon” name and public identification mark on products or packaging, indicating the fruit name, origin, producer, or seller. Watermelons should be handled gently. They are not suitable for long-term storage and, if temporarily kept, should be placed in cool, dry, ventilated areas or stored in temperature-controlled warehouses. Transport should use dedicated vehicles, protecting against sun and rain exposure.