Onion is one of the daily required vegetable in the world. Although a perennial plant, Onion crop is generally cultivated as an annual plant. India is the second largest country to produce onions where Maharashtra, Madhya Pradesh, Karnataka, Gujarat etc, contribute to the major production. This crop requires different climatic conditions and can be harvested within 3 to 5 months. Usually called as common onions or bulb onions, these can be available in red, white and yellow color. So lets see what are the different stages of its cultivation.
- In India onion is both kharif and rabi crop. These onions require friendly climatic conditions, that is not too much of cold, heat and rainfall.
- Mostly it can be grown in tropical and subtropical climate with a temperature range of 13 to 25oC and annual rainfall range of 600 to 800mm. According to experts, it requires 70% of relative humidity for better growth.
- Well drained fertile soils are most convenient for onion cultivation. Apart from that soils with low sulfur and high nutrition are also ideal for its growth.
- Basically soils which has pH range of 6.5 to 8 with good moisture and sufficient organic manure are also apt for onion crop.
- As usual land is ploughed to fine tilth without any weeds and wastes. At the final tillage add 8 tons of vermicompost or 15 tons of farm yard manure per hectare.
- After that flat beds of 2m width and 5m length are formed or broad bed furrows of 20cm height 115cm width are made depending up on the soil type.
- Usually Broad bed furrows are preferred during rainy seasons as the excess water storage leads to certain diseases.
- Onions can be grown either from seeds or bulblets. For this, separate nursery should be maintained with appropriate manure adding and water facilities.
- According to experts approximately 7kg seeds are required to raise the seedlings per hectare.
- Within one to two months seedlings are ready to transplant on to the main field.
- Apart from the seeds, previous high quality onion bulbs that are stored in well conditions can also used for transplanting.
- Later the seedlings are to be planted by maintaining a distance of 15cm between the rows and 10cm between each plant.
- Irrigate the entire field before transplanting the seedlings. After two days of transplanting, again one more time watering should be done.
- From now on, carry the irrigation process at weekly intervals, but make sure that too much water logging is not happening.
- Finally, remember to stop the irrigation before 10 days of harvesting process.
- Weeds are the primary concern in onion cultivation. As the weeds are mingled with onion leaves, it is a very difficult process to carry.
- But for getting a good yield, controlling weeds is must. You can do it manually or by spraying chemicals.
- Also onion fly, cut worm and thrips cause great damage to this crop. According to experts spraying insecticides can solve this threat.
- Apart from these, Leaf spot and Basal rot are the main diseases that affect the crop drastically. Consult the farming experts and adopt the appropriate method to eradicate these diseases.
- For improving the fertility of the soil, maintaining crop rotation is necessary in onion cultivation. Particularly soybeans are considered as the suitable one for crop rotation.
- When the onions stop producing new leaves think that they are ready to harvest.
- Irrigation should be stopped before 10 days of harvesting.
- But the harvesting phase depends on various factors like season, type of the variety used etc.
- After removing from the land, these onions are exposed to sunlight for two to three days to remove excess water.
- Usually a kharif crop gives approximately 20 tons of yield per hectare while a rabi crop gives nearly 30 tons per hectare.
- Finally the onions are stored in gunny bags to ensure appropriate air and light.