The key to the cultivation of sweet and tender onions lies in the selection of varieties, soil treatment, management of water fertilization and timely harvesting. Onion varieties (e. G., four-season onions) are recommended to maintain soil sterilisation and fertility, pre-harvest control of perfumes, and growth cycle control in 30 to 40 days。
1. Choice of varieties
Select the fine and fragrance varieties:
• four seasons of onions: cold and hot, long-smelt, suitable for family cultivation
• onions with red head: purple onions, more windy
Avoid the use of onions or onions, which are thicker and smell less。
Soils and cultivation
• soil formulation: by corrosive soil: river sand = 3:1 mixed with 1 kg of decomposition dung per square metre (recommended ratio of organic farming norms for the ministry of agriculture and rural, 2024)
• scrolling techniques: 15 cm long and no more than 1 cm thick of the earth; 8-10 cm distance of the seedling plant
• light-shielding: 3-5 days of seeding cover-covered lumber promotion with a 20 per cent increase in gerontization
3. Fertilizer management
• fertilizer recovery programme: application of high nitrogen water solution (n-p-k=20-5-5) 20 days after seeding, diluted by 1,000 times weekly spraying
• water control techniques: cessation of water irrigation three days before harvest, at which point onion dry matter can accumulate up to 12-15 per cent (in experimental data from the china agricultural institute, 2023) and increase in the concentration of fragrance material by 30 per cent
4. Timing of harvest
- best harvest period is 20-25 cm high, at which point the stem is about 2-3 mm in diameter
- in the morning, when the dew is dry, the fragrance remains intact
- putting a pair of scissors on the ground and keeping 1 cm of the base will facilitate a second stroke
5. Pest management
When a leach fly is found, it is removed immediately and 500 times more liquid is sprayed with 5% bitter alkaline. The use of chemical pesticides is avoided, otherwise it affects the formation of wind。
In the case of pelvis cultivation, it is recommended to select containers of 15 cm depth, not more than 20 per basin. It is necessary to cover the summer afternoons in order to prevent the aging of foliage。
