Reasonable fertilization is required for any crop, and the basis for reasonable fertilization is determined based on soil characteristics, planting environment, and fertilizer requirements, and green onions are no exception. Therefore, when it comes to what kind of fertilizer is good for green onions, you must first understand the fertilizer requirements of green onions, and then select fertilizers suitable for the growth of green onions based on the actual local planting conditions. Only in this way can the production of green onions achieve higher yields and quality.

1. Fertilizer requirements of green onions

1. Requirements of green onions for growth environment

The roots of green onions are white string-like fibrous roots with uniform thickness and divided into There are few lateral roots. Although the ability to absorb fertilizer is weak, it needs more fertilizer and is a fertilizer-absorbing crop. The temperature required for the growth of green onions is 7~35℃, but the most suitable temperature for the growth of green onions is 19~25℃. Within this temperature range, the growth is fastest; green onions are drought-tolerant but not waterlogging-resistant, and the plant has strong water retention capacity. It consumes less water; green onions do not have strict requirements for light. As long as the plant can pass through vernalization normally, it can bolt and bloom normally in both short- and long-day environments; green onions do not have strict requirements for soil, and green onions are suitable for growth. The soil pH is 7~7.4.

2. Nutrient requirements of green onions

Under normal circumstances, the production of 1,000 kilograms of green onions requires the absorption of pure nitrogen, phosphorus, and potassium, which are 2.5 to 3 kilograms, 0.5 to 1.2 kilograms, and potassium, respectively. 3.3~4 kg. From this we can see that green onions have the highest demand for potassium fertilizer, followed by nitrogen fertilizer, and the least absorption of phosphorus fertilizer. Among the three major elements, green onions are the most sensitive to nitrogen. Reasonable application of nitrogen fertilizer can significantly increase the yield of green onions.

Among the medium and trace elements, green onions are relatively sensitive to calcium, sulfur, boron, manganese, etc. Especially sulfur, the pungent taste of green onions is due to the sulfide content. Therefore, if the green onions lack sulfur during their growth and development, it will inhibit the synthesis of sulfides, thus reducing the quality of the green onions. Therefore, when top dressing green onions, it is best to choose sulfur-containing fertilizers, such as potassium sulfate, etc., which can not only supplement other nutrients but also supplement sulfur, thus improving the flavor of green onions.

Green onions absorb nutrients differently at different growth stages. Green onions grown in northern my country are either sown in autumn or sown in spring, but are generally harvested in November of the following year.

Since the seedling stage of overwintering green onions is in winter, their growth volume is small and their absorption of nutrients is also relatively small. If sufficient base fertilizer is applied, additional fertilization is not needed. Too much fertilizer will cause It will cause leggy growth, which is not conducive to the smooth wintering of green onions. After turning green in spring, the growth of green onion seedlings is the most vigorous, and it is also a critical period for the formation of strong seedlings. If it is to produce green onions, it is also a critical time point for the formation of green onion yields. Therefore, more fertilizer is required.

Generally, planting begins in June of the second year. After planting, green onions enter the period of green onion formation. In the early stage, because it is the growth recovery stage, the amount of fertilizer required is not very large, but as the weather changes, When the weather is cool, the daytime temperature difference increases and the growth rate begins to accelerate. Therefore, this stage is also a critical period for fertilizer needs. It is also a period when the soil is softened and yields are formed. At about 11 minutes, due to the sharp drop in temperature, the green onion plants began to stop growing, the leaves and roots gradually aged, and the nutrient absorption decreased rapidly.

2. How to fertilize green onions

Green onions are suitable for planting on fertile soil with deep soil and strong water and fertility retention. Due to the long growth period, in addition to sufficient base fertilizer, , it is also necessary to carry out multiple top dressings at different growth stages to ensure the robust growth of the plants.

1. Base fertilizer for green onions

The base fertilizer should be spread and plowed into the soil before land preparation, and ensure that the soil and fertilizer are fully mixed. Apply about 3,500 kilograms of decomposed organic fertilizer per acre, 40 dry grams of superphosphate, 20 kilograms of potassium sulfate, or 100 kilograms of plant ash in areas where conditions permit. In addition, in order to ensure nutrient balance, 2 dry grams of copper sulfate and 1 kilogram of boric acid can be applied per acre when applying base fertilizer.

2. Top-dressing of green onions

Top-dressing should be carried out in combination with cultivating, soil-building and watering of green onions. The principles to be grasped are light first, medium heavy and top-up later.

The fertilization period is around the Bailu solar term. This period is the vigorous growth period of green onion leaves. Fertilization ensures leaf growth, thereby improving the yield and quality of green onions. In the first top dressing at the beginning of autumn, apply 3000~4000 kg of soil fertilizer or 150~200 kg of cake fertilizer per acre. Nitrogen fertilizer, such as about 15 kg of urea, can also be applied.

Start the second top dressing during the summer season. This time, additional phosphorus and potassium fertilizers should be applied. You can apply 50 to 100 kilograms of cake fertilizer, 30 kilograms of superphosphate, and 100 kilograms of plant ash per acre, and after fertilization, Carry out cultivating and cultivating the soil.

When green onions enter the growth stage, it is an important period for the formation of green onions. Since green onions grow larger, they also have greater demand for nutrients. Top dressing can be carried out during the white dew and autumnal equinox seasons to promote growth. Green onions sprout. Therefore, the third top dressing is carried out during the white dew season. The top dressing is mainly nitrogen fertilizer and potassium fertilizer. Apply 10 to 15 kg of urea per mu, 100 kg of plant ash or 10 to 15 kg of potassium sulfate. For the fourth top dressing during the autumnal equinox, 15 to 20 kilograms of urea or 20 to 30 kilograms of compound fertilizer, 100 kilograms of plant ash or 10 to 15 kilograms of potassium sulfate can be applied per mu.

The fibrous roots of green onions have the characteristics of fattening, water-tending and temperature-tending. Therefore, this characteristic can be combined with scientific and reasonable fertilization when fertilizing.

A farmer friend has a saying that sums it up well: "Spread by the roots, cultivate the soil and press it, and water it." That is to say, when fertilizing, the fertilizer should be spread evenly on the topsoil of the roots of the green onions, and then the roots of the green onions should be covered with soil to cover the fertilizer. This can reduce the loss of nutrients and promote the absorption of nutrients by the fibrous roots, thereby promoting the soft growth of the green onions and improving the plant's resistance. In order to reverse the problem, watering within two days after soil cultivation is beneficial to the dissolution of fertilizer and accelerates the absorption of nutrients by green onions.

In order to improve the stress resistance of young seedlings, it is also necessary to supplement nutrients through extra-root top dressing. In production, the plant ash filtrate can be sprayed on the leaves. The specific method is to dissolve 8 kilograms of plant ash in 15 kilograms of water. After filtering, add 150 kilograms of water to the leaf surface for spraying. Once every 7 to 10 days, spray continuously for 2 days. ~2 times. You can also spray 0.2% potassium dihydrogen phosphate solution through the page to enhance the growth potential of the seedlings and improve the plant's disease and wind resistance.

In the process of fertilizing green onions, scientific and reasonable fertilization must be carried out based on the nutrient requirements and growth characteristics of green onions, as well as soil fertility, climate characteristics, etc. Only in this way can the normal growth and development of green onions be promoted. In order to obtain higher yield and quality.