How can onions be cultivated for high yield?

How to cultivate onions for high yield and what good methods are there? Also ask experienced netizens to help introduce the farming network summed up three onion cultivation methods, can effectively improve onion production, the following detailed list for netizens' reference. Method 1. Cultivate strong seedlings at the right time: the suitable sowing date of onion is about September 20, the bolting rate of early sowing is high, and it is easy to suffer frost damage if sowing too late. 300 grams per mu for direct seeding and 50 grams for every 10 square meters of seedlings. First draw a shallow ditch on the finished border surface, then spread the seeds evenly into the ditch, cover the soil 1 cm thick after sowing, water it after stepping on it, irrigate the second water on the fourth day after sowing, and pour the third water on the eighth day when the border surface sprouts, to ensure that the seedlings are evenly watered. Watering the seedlings with small water every 7-10 days and pulling the grass. Reasonable seedling spacing, 3-4 cm apart. When there is harm to mole cricket, add appropriate amount of poisonous silk when watering, and pay attention to the prevention and control of Botrytis cinerea. After 30 days of seedling growth, a small amount of urea and potassium dihydrogen phosphate could be applied. Method 2. Select the planting time of onions: the suitable planting period of onions is in the first ten days of November, and the standard seedlings should be graded first, and then the seedlings should be planted. The planting depth should be appropriate, the deep bulb is easy to form a spindle shape, and the yield is low; too shallow and easy to lodge, it is appropriate to bury the bulb about 1 cm. Avoid continuous cropping of onions and apply 4000 kg of fully mature organic fertilizer, 50 kg of diammonium phosphate and 30 kg of potassium sulfate per mu. After fertilization, the land will be leveled and raked fine and made into a flat border, and the width of the border will be determined according to the width of the plastic film. It is generally planted about 23000 plants per mu according to the row spacing of 20 cm × 15 cm. Water before covering the plastic film, and then punch holes in the film with a depth of 3 cm and a diameter of 1.5 cm. When planting, insert the onion seedlings directly into the hole, press them with your hands, and seal the hole. If it is not covered with plastic film or not watered before mulching, it shall be watered in time after planting, and slow seedling water will be watered again in 4-5 days. Method 3. Scientific management: watering once before soil freezing; watering back to green water when onion seedlings turn green in late February of the following year; watering times during bulb expansion period should be increased, generally once every 6-8 days, to keep the ground dry and wet, so as to facilitate bulb expansion; stop watering 10 days before harvest to facilitate storage. Potassium and nitrogen fertilizers were applied with watering to promote the early development of seedlings, and the bulb expansion stage was the key period of topdressing, topdressing 15 kg urea and 20 kg potassium sulfate per mu in late April and mid-May respectively. Sowing early in autumn, the seedlings are too large or in a warm winter year, onions are easy to cause early bolting through vernalization. In this case, the bolts can be pinched off from under the expansion of the bolts. It is found that onions with two heads growing in the field can remove one head and let the other head continue to grow. Onion plants should not be trampled down during the bulb expansion period, otherwise the normal operation of nutrients will be affected and the yield will be reduced. Click to get more onion planting techniques click to get more vegetable planting techniques