What fertilizer is good for green onion topdressing?

Time for topdressing green onions

After the Beginning of Autumn, after the White Dew, and after the Frost Descent, the best time to apply top dressing to green onions is in late August, early September, and early October.

What fertilizer to use for green onion topdressing

Green onions have a large demand for nutrients and generally require the application of pure nitrogen, phosphorus pentoxide, and potassium oxide. The absorption ratio of nitrogen, phosphorus, and potassium is 1:0.4:1.3. They are very sensitive to potassium and nitrogen nutrition, so focus on the use of nitrogen fertilizer and potassium fertilizer in topdressing. When preparing the land, you can apply high-nitrogen and high-potassium potassium sulfate fertilizer to increase the yield of green onions.

Should I use urea or compound fertilizer for topdressing green onions?

During the vigorous growth period of green onions, it is mainly necessary to apply fertilizers containing nitrogen and potassium. Nitrogen can improve the leaves of green onions, and potassium fertilizer can improve the quality of pseudostems, so it is best to use compound fertilizers.

Method of topdressing green onion

Before planting green onions, sufficient base fertilizer should be applied. You can apply fully decomposed organic fertilizer. For soils with low phosphorus and potassium content, add calcium phosphate, wood ash or potassium sulfate. In addition, copper phosphate and boric acid can be applied.

Principles of topdressing for green onions

The method of fertilizing green onions should be based on the principle of "applying less fertilizer and more times", and topdressing should be done 3 to 4 times from planting to harvesting.

Dosage of topdressing for green onions

If the soil where green onions are grown contains low potassium, the amount of potassium fertilizer should be appropriately increased. In addition, the amount of topdressing should depend on the target yield. At high yield levels, such as an output of more than 10,000 jin per mu, the amount of potassium taken away from the soil by green onions each season is high, and potassium fertilizer needs to be supplemented in time.

Precautions for topdressing green onions

The principle of topdressing green onions is "light at the beginning, heavy in the middle, attack in the middle and supplement in the end".

1. After transplanting, during the summer seedling growth period, no watering and fertilization are required. Only shallow tillage and loosening of the soil are required. When the climate turns cooler after the beginning of autumn, the growth of the plants gradually accelerates. Top dressing should be applied once with nitrogen, phosphorus and potassium compound fertilizers or urea, potassium sulfate, or decomposed organic fertilizers.

2. Early September is the period of vigorous growth of green onions, and the white part of the green onion enters the peak growth period. At this time, the demand for fertilizer is great, and the second topdressing should be carried out, applying compound fertilizers of nitrogen, phosphorus and potassium, or applying decomposed human manure, or spreading ammonium humate, superphosphate, and wood ash. The third topdressing should be carried out in late September or early October, applying urea. After topdressing, water and cultivate the soil until harvest.