Is it OK to grow oranges in Cangzhou, Hebei Province?

planting oranges in Cangzhou: large-scale planting can't solve the winter cold problem, so it can only be done in greenhouses or flowerpots. South Korea and China are one of the important origins of citrus, which is rich in citrus resources and has a variety of excellent varieties, and has a cultivation history of more than 4, years. As early as the Xia Dynasty (from the 21st century to the 17th century), oranges produced in Jiangsu, Anhui, Jiangxi, Hunan, Hubei and other places in China have been classified as tribute. After long-term cultivation and selection, citrus has become a precious fruit of human beings. According to research, it was not until 1471 AD that oranges, tangerines, oranges and other citrus fruit trees were introduced from China to Lisbon, Portugal, and it was introduced to Florida, USA in 1665 AD. In China, Huangyan, Taizhou City, Zhejiang Province is a hometown of tangerines. Citrus in the world is mainly distributed in the area south of 35 north latitude, which likes to be warm and humid. The area with large water body warming can be pushed northward to 45 north latitude. The growth, flowering and fruiting of citrus fruit trees are closely related to environmental conditions such as temperature, sunshine, moisture (humidity), soil, wind, altitude, topography and slope direction, which affect the maximum temperature. Even if the temperature difference is .5℃, sometimes there will be completely different results. The growth and development of citrus requires a temperature of 12.5 ~ 37℃. In autumn, flower bud differentiation requires that the temperature of day and night is about 2℃ and 1℃ respectively, and the soil temperature for root growth is roughly the same as that of shoot. If the temperature is too low, the citrus will be frozen. When the sweet orange is -4℃ and the satsuma is -5℃, the branches and branches will be frozen. When the sweet orange is below -5℃ and the satsuma is below -6℃, the plants will freeze to death. High temperature is also not conducive to the growth and development of citrus. When the air temperature and soil temperature are higher than 37℃, the fruits and roots stop growing. Temperature also has obvious influence on fruit quality: in a certain temperature range, sugar content and soluble solids increase, acid content decreases and quality becomes better with the increase of temperature. Citrus is a tree species with strong shade tolerance, but good sunshine is still needed for high quality and high yield. Generally, areas with annual sunshine hours of 12 ~ 22 hours can grow normally. For example, compared with Chongqing citrus producing area with less sunshine, South China with good sunshine and abundant calories has higher sugar content, lower acid content and higher sugar-acid ratio. Generally, tropical and subtropical regions with annual rainfall of about 1 mm are suitable for citrus cultivation, but irrigation is often needed because of uneven distribution of annual rainfall. The suitable relative water content of soil is 6% ~ 8%, and if it is lower than 6%, it needs irrigation. Too much rain will cause soil water accumulation or high groundwater level and poor drainage in citrus orchards, which will cause root system death. Citrus fruit trees require that the air relative humidity should be about 75%. Citrus can adapt to a wide range of soil. Purple soil, red and yellow soil, beach and beach can all grow at pH 4.5 ~ 8, and pH 5.5 ~ 6.5 is the most suitable. The growth of citrus roots requires high oxygen content, and the soil with loose texture, good structure, organic matter content of 2% ~ 3% and good drainage is the most suitable.