The seedling raising time of Shandong Welsh onion is generally in the first ten days of September, overwintering as seedlings, planting in early summer of next year, and harvesting before winter. Soil hardening should be prevented when green onions emerge, and topdressing should be done once after emergence to promote growth.
Planting method of Shandong Welsh onion
1, soil
Onion is suitable for loam cultivation with pH of pH6.5-7.5. The nursery site requires loose fertilizer and sufficient soil moisture, and the surface soil should be prevented from hardening at seedling stage. When seedlings begin to grow rapidly, topdressing should be done once, and soil moisture should be controlled10-0/5 days before planting to prevent overgrowth and lodging.
2. Fertilizer
Onion likes fertilizer and requires balanced application of nitrogen, phosphorus and potassium. There are more requirements for nitrogen fertilizer in the early stage of growth, and more phosphorus and potassium fertilizer are needed in the later stage. Pay special attention to the application of phosphate fertilizer, because the lack of phosphate fertilizer will lead to poor plant growth and decreased yield. At the same time, we should pay attention to the content of sulfur in onion field, and the lack of sulfur in soil will affect the effect of increasing production.
3. Temperature
Welsh onion is resistant to stress, both cold and heat. Although temperature has little effect on the growth of green onions in general, suitable temperature conditions are conducive to high quality and high yield.
4. Moisture
Welsh onion has less root hair and poor water and fertilizer absorption ability. Roots are mostly distributed in the surface layer of soil, which likes humidity and requires high soil humidity, but roots are afraid of waterlogging, and high temperature and humidity can easily cause root death.
5. Lighting
Onion requires moderate light intensity. Because the tubular leaves of green onions can still get good lighting conditions under the condition of close planting, there is no need for strong light. Strong light has an adverse effect on the growth of green onions, which will lead to the aging of leaves, the increase of fiber, the decline of quality and even the loss of edible value.