The main crops here include early rice, first season rice, late rice, winter wheat, spring wheat, spring corn, summer corn, rape, cotton, and soybean. See the table below for the area planted with some crops.
 Sown area of some crops in China in 2004  Thousand hectare
Grain corn, winter wheat, one season, rice, soybean, late rice, early rice, spring wheat
25446 19952 16068 9589 6364 5946 1674
Cash crops of vegetables, melons, cotton, rapeseed tobacco herbs sugar peanut
19708 7272 5693 4745 1568 1285 1266
According to years of agricultural meteorological reports and related data, the author speculates that the nitrogen fertilizer fertilization period in China is as follows:
　　
　　 January-February: part staple crops fertilizer began to mainly rape. Part of the southwestern winter wheat is returning to the green. From the southwest, the south of the Yangtze River to the Jianghuai, the northwestern part of the rapeseed successively entered the buds and fertilizers. A small amount of early rice in South China began to plant base fertilizer from south to north.
　　
　　 March : The start-up period of spring tillage and fertilization season is mainly in the south, and the north is also increasing. Rice and winter wheat are the key points. ,
　　
Some of the winter wheat in the northwest, Huanghuai and Jianghuai are green and topdressed, and the winter wheat in the southwest and Jianghan are part of the winter wheat. Partial spring wheat in the northwest and north China was planted with fertilizer. Some of the rapeseed in Jianghuai and Jiangnan are still chasing the moss. Some of the South China, Jiangnan, Southwest, and Huazhong spring corn were planted with fertilizer. Part of the rice in the southwestern part of the country began to plant the bottom fertilizer. In the southern part of South China, some early rice returned to green tiller and topdressed, and most of southern China and Jiangnan planted base fertilizer.
　　
　　 April : During the peak season of spring tillage and fertilization, a large number of crops are fertilized.
　　
Winter wheat with a large planting area enters the peak period of returning greening, mainly in the areas of Jianghuai, Huanghuai, North China and Northwest China. Spring wheat is mainly planted in the north and northwest of China. Spring corn is planted in the northeast, northwest, north China, Jianghuai, Jianghan, southwestern part of the production area, the semi-finished fertilizer in the Yangtze River Basin and South China. Cotton began to plant a large amount of base fertilizer, mainly in the Xinjiang, Huanghuai and Yangtze River basins. In the peak season of rice planting in the first season, the northeast, Jianghan and Jianghuai are partially planted with fertilizer. Early rice enters the peak season of topdressing, and the southern part of South China catches up with the ear fertilizer. Most of southern China to the south of the Yangtze River continue to enter the green season.
　　
　　 May : Relative to the lighter season in April .
　　
Only a small amount of winter wheat in the north is still topdressing. Spring wheat, which is relatively small in winter wheat planting area, has only partially entered the topdressing period. Spring corn is the main fertilizer crop this month. A large amount of northeast corn with large planting area is planted from the middle and lower reaches of the Yangtze River, southwest to north China, and northwestern part of the gradual large topdressing period. In southern China, a small amount of topdressing has been introduced. Summer corn is planted in small quantities in the southwest and Huanghuai areas. A small amount of cotton production area is small chasing bud fertilizer. One season of rice in some areas such as Jianghuai is still being planted, and the southwest and northeast parts are turned into green tillers. Early rice topdressing is also the focus of this month. Most of South China and Jiangnan have been chasing green glutinous fertilizers to catching panicles. Late rice began to be planted at the southern end of South China.
　　
　　 June : In the peak season, it is mainly used for rice and corn.
　　
The northeast, northwest, and north China spring wheat have been heavily fertilized and fertilized. Most of the northeast, northwest, and north China spring corn entered the peak season of heavy fertilizer, and the south of the Yangtze River and the southwest entered the small topdressing period. Summer maize in North China is planted with fertilizer, and the southwest enters the big fertilizer season. Most of the cotton in Xinjiang, Huanghuai and the Yangtze River are chasing the buds. One season of rice topdressing season, southwest chasing fertilizer, most of the northeast, Jianghuai, Jianghan and so on. In the early rice season, the south and south of the Yangtze River were completed. Late rice continues to be planted in the south and south of South China.
　　
　　 July : In the peak season, mainly rice, summer corn, and cotton fertilizer.
　　
In the northeast, northwest, and north China, the spring corn is generally divided into small top dressings during the tasseling period. Summer maize has been rapidly topdressed by the southwest, Huanghuai, North China, and Northwest China. Cotton enters the flowering and boll period of heavy fertilization in Xinjiang, Huanghuai and Yangtze River basins. Soybeans in the northeast and north China have entered the flowering and topdressing period. In the southwest, Jianghan, and northeastern part of the rice, the rice is followed by panicle fertilizer. Some late rice in South China is still being planted, and some parts of the south of the Yangtze River have begun to return to the green.
　　
　　 August : The peak season fades.
　　
Northern spring corn basically completed small topdressing in the first half. Northern summer corn also has some small top dressing and ends fertilization. Most of the cotton is in the flowering and boll period of heavy fertilization in Xinjiang, Huanghuai and Yangtze River basins. In the northeast, Jianghuai, Jianghan and other parts of the rice, the rice is gradually completed. Most of the late-season rice in South China and the south of the Yangtze River are top-harvested and topdressed.
　　
　　 In early September - November: fertilization small off-season.
　　
In the bulk crops, winter wheat is planted in the northwest, north China, Huanghuai, Jianghuai, Jianghan and southwestern areas. Rape is also planted in the northwest, the middle and lower reaches of the Yangtze River, and the southwestern areas. Late rice was followed by panicle fertilizer in Jiangnan and South China in September .
　　
　　 Mid - November - December : Low season.
　　
There is almost no large crop fertilizer in this season (but economic crops such as vegetables in greenhouses and tropical areas may use fertilizer).
　　
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