Seedlings should be screened before planting, and diseased plants, disabled plants and weak plants should be eliminated. After screening, cut off the tip of fibrous roots, leaving 2 ~ 3 cm to promote the development of new roots. Transplant according to the row spacing of 20cm and the plant spacing of 10cm, and plant 4-6 plants at a time. Spring onion and autumn onion can be planted thinly, and the planting should be shallow, about 3-5cm, and the planting water should be poured in time after planting.
The root system distribution of shallot is shallow, and its absorption capacity is weak, so it is not tolerant to concentrated fertilizer and drought and flood, so it needs to be watered frequently, and attention should be paid to the drainage of accumulated water after rain. After the seedlings are delayed at a fixed value, it should be combined with watering in time for topdressing, usually applying 5 kg of urea or 0/5 kg of ammonium bicarbonate 10 days-/kloc-. Foliage fertilizer can also be used to promote the green of onion plants.
Extended data:
Pests are mainly controlled by onion maggots, leaf miners and thrips, and diseases are mainly controlled by epidemic disease, downy mildew and gray mold. Pest control should master the principle of prevention first and comprehensive management, adopt agricultural and biological control measures, use chemical pesticides scientifically, coordinate various control technologies and give full play to comprehensive benefits.
In addition, when we increase the application of organic fertilizer, we should water it in time for topdressing, and it is best to apply more phosphorus and potassium fertilizer, less nitrogen fertilizer, and keep the stubble well. It takes about 40 days for shallots to turn green to the first cut (when the plant height is 30 ~ 50 cm), the second cut takes about 30 days, and the third cut takes about 25 days.
When harvesting shallots, it is best to do it on sunny days or in the evening. The cutting edge of shallots should be 2-3cm away from the ground and the cutting edge should be neat and consistent. After each harvest, rake the ground with a rake for l times. After 3 days, the wound of shallots should be healed and watered immediately. Avoid harvesting during the summer solstice to prevent seedlings from dying.
When the leaves are luxuriant, they can be harvested and eaten, and the leaves above the leaf sheath can be picked by hand, and the smaller leaves in the middle can be kept for continuous growth. When most of the leaves become Huang Shi, the bulbs are dug out, the leaves are dried and stored in a ventilated place, and the bulbs can be used for further reproduction.