Shandong province is located in the most suitable area for the growth of green onions. It has been famous for its abundant green onions since ancient times, so it is called "Green Onion Province". Among them, Jinan Zhangqiu scallion is famous for its "high, large, crisp, white and sweet" and has a planting history of more than 2,000 years, and is known as the "king of scallions". Shandong province has cultivated many varieties of high-quality green onions, such as Zhangqiu green onions and Qingdao green onions. These varieties have the characteristics of strong growth potential, strong insect resistance and high yield, and are deeply loved by farmers and consumers.
Onion planting industry in Shandong province has formed a complete industrial chain. There is a mature system from planting, processing to sales. Farmers can sell fresh green onions directly to wholesalers or supermarkets, or make pickled green onions or other products through primary processing to increase added value.
Brief introduction of onion growth habits
Onion is native to semi-cold zone, which has a wide range of temperature adaptation, likes cold but is not heat-resistant, and can obtain good yield and quality under cold and warm conditions. The most suitable temperature range for the growth of Chinese onion is 13-25℃, the highest temperature is 45℃, and the Chinese onion has strong cold tolerance, and the lowest temperature is MINUS 20℃. The vernalization temperature is 2-7℃, and the general vernalization time is 7- 10 day.
When the temperature is in the range of 2-5℃, seeds can start to germinate, and the optimum temperature for seed germination is 15-20℃. In this range, the higher the temperature, the faster the germination. When the temperature is higher than 20℃, the germination rate is affected. Onion leaves can grow at 15-25℃, and the most suitable temperature for leaf growth is 10-20℃. In this temperature range, green onions grow rapidly and vigorously, which is beneficial to the accumulation of nutrients in leaf sheaths, with strong stems and leaves and good quality.