What fertilizer is best for green onions (What fertilizer is best for growing green onions at home)

In order to achieve high yield in green onion cultivation, fertilization management is a very important part. Green onion high-yield fertilization technology is a cultivation technology that increases green onion yield through scientific fertilization. On the basis of not damaging the soil environment, it maximizes the production potential of green onions, thereby achieving the purpose of increasing production and income.

Fertilizer requirements of green onions

Green onions are shallow-rooted crops, with roots mainly distributed within 30 cm of the topsoil. They have strong adaptability to soil, but high yields are easiest to obtain in sandy loam that is loose, breathable, and rich in organic matter.

Although the green onion root system has a weak ability to absorb fertilizer and water, it is a fertilizer-loving crop, with the absorption ratio of nitrogen, phosphorus and potassium being (65~75): (13~15):100.

Generally, the production of 500 kg of onions requires 1.5 kg of nitrogen, 0.61 kg of phosphorus, and 2 kg of potassium. It can be seen that the demand for potassium fertilizer is the greatest.

However, onion plants that lack nitrogen and phosphorus grow poorly, so attention should be paid to increasing the application of nitrogen and phosphorus fertilizers during production. In addition, sulfur, calcium, magnesium, manganese, and boron have a significant impact on the yield and quality of onions.

Fertilization management should be based on applying sufficient base fertilizer and topdressing according to the fertilizer requirements of each growth period.

It is recommended that base fertilizer be mainly organic fertilizer, with a complete combination of nitrogen, phosphorus and potassium, and attention should be paid to the application of trace fertilizers. Top dressing should be mainly quick-acting nitrogen fertilizer, with the focus on light fertilizer at the beginning and heavy fertilizer at the end, attacking in the middle and supplementing at the end.

Fertilization management technology of green onion

In order to achieve the year-round supply of green onions, green onions are cultivated in different rotations. According to the different harvest times, the main rotations of green onions are open field cultivation in autumn and winter, delayed cultivation in greenhouses in autumn, and early cultivation in greenhouses in spring. Affected by factors such as climate and cultivation environment, fertilization management should also be treated differently.

1. Onion base fertilizer application and management technology

Base fertilizer provides the nutrient basis for the growth and development of green onions throughout the year, and requires neither partial application nor comprehensive nutrients.

Application technology of base fertilizer in open field cultivation in autumn and winter

In northern my country, autumn sowing is generally used, while in southern China, spring sowing is mainly used, but autumn sowing is also possible. However, whether it is autumn sowing or spring sowing, it is planted in mid-to-late June to early July. After the previous crop is harvested, deep plowing and sunning the soil in time to kill pathogens in the soil.

In combination with land preparation, apply 4500 kg of farmyard manure or 3000 kg of rice husk chicken manure or 750 kg of commercial organic fertilizer per mu, 50 kg of superphosphate, 50 kg of potassium sulfate type ternary compound fertilizer with a ratio of 15-15-15, and 4 kg of medium and trace element fertilizer, and adopt wide row and dense planting.

Technology of applying basal fertilizer for delayed autumn and early spring cultivation in greenhouse

Late autumn and early spring cultivation in greenhouses generally adopt the method of shallow soil cultivation with narrow rows and small ditches.

After the previous crop is pulled out, deep plowing and land preparation should be combined with applying 8,000 to 10,000 kg of decomposed farmyard manure or 1,000 kg of commercial organic fertilizer per mu (if it is commercial organic fertilizer, it can be applied in a targeted manner by digging trenches).

After raking the ground, dig furrows from north to south. The furrows are 25cm deep and 30cm wide, with a distance of 1m between furrows. In combination with digging furrows, apply 25kg of potassium sulfate-type ternary compound fertilizer per mu, and dig it into the soil by hoeing to evenly mix the fertilizer and soil.

2. Management technology of topdressing for green onion

Top dressing of green onions should be carried out flexibly according to soil moisture conditions, the amount of base fertilizer applied and the growth of the plants.

Topdressing technology for open-field cultivation in autumn and winter

After planting, green onions enter the seedling stage, which takes about 1 month. If the weather is not dry during the seedling stage, watering and fertilization are generally not required. If necessary, a small amount of water can be poured 15 days after planting to promote new roots.

After entering the leafing period (early August to late August), the plant begins to increase its demand for water and fertilizer. Depending on the condition of the seedlings, foliar fertilizer can be applied in combination with watering and soil cultivation.

The first topdressing should be carried out after the pseudostem enters the growth period in early August. 50-100 kg of granular organic fertilizer, 10-15 kg of ammonium sulfate or urea, 5 kg of potassium sulfate or 20 kg of potassium sulfate-type triple compound fertilizer can be spread per mu on the ridge furrows and ridge backs.

In late August, when the onion seedlings enter the tubular leaf growth period, 10-15 kg of urea and 15-20 kg of potassium sulfate can be spread in the ridges.

Green onions enter their peak growth period from early September to mid-to-late October. Topdressing should be done in time around the White Dew in early September, with 10-15 kg of urea, 10-15 kg of potassium sulfate, 20 kg of superphosphate or 30-50 kg of potassium sulfate-type triple compound fertilizer applied per mu.

After top dressing, bury the fertilizer with soil. The depth should be enough not to cover the onion heart. Make a ditch on the back of the ridge. Water the ditch after fertilizing.

In late September, the pseudostem enters a period of significant expansion, which is also the peak period for water and fertilizer demand. Before and after the autumnal equinox, soil should be cultivated once according to the length of the pseudostem.

Apply 15-20 kg of urea, 15-20 kg of diammonium phosphate, 10-15 kg of potassium sulfate or 30-50 kg of potassium sulfate-type triple compound fertilizer in the ridges, combine it with inter-tillage, cover fertilizer and water.

In addition, for soils with severe boron deficiency, 0.5% borax solution can be sprayed on the leaves in combination with disease and pest control, once every 10 days, for 2 to 3 times in a row.

Topdressing technology for delayed autumn and early spring cultivation in greenhouses

• Seedling fertilizer: 20 days after the onion seedlings are planted, they will pass the seedling growth period. At this time, you should apply fertilizer to promote seedling growth in combination with watering. Apply 15-20 kg of urea per mu.

• Foliar fertilizer: In the early stage of pseudostem growth, foliar fertilizer should be applied. 25 kg of potassium sulfate type ternary compound fertilizer, 10 kg of urea or 10 kg of high-nitrogen macro-element water-soluble fertilizer should be applied per mu. The recommended ratio is 30-9-12+TE.

• Fertilizer for tree growth: During the peak period of pseudostem growth, the fertilizer requirement increases, and fertilizer for tree growth can be applied in 2-3 times in combination with soil cultivation. Apply 50 kg of potassium sulfate type triple compound fertilizer, 20 kg of urea, 20 kg of potassium sulfate, or 1 time of high nitrogen type macronutrient water-soluble fertilizer (ratio is 30-9-12+TE) and 10 kg of high potassium type macronutrient water-soluble fertilizer (recommended ratio is 14-8-35+TE) per mu.

Although green onions are shallow-rooted crops, they are relatively fertilizer-loving. In the cultivation and production of green onions, ensuring the standardized application of high-yield fertilization technology will play an important role in promoting both the yield and economic benefits of green onions.