Onions are a cold-season crop, easy to grow because of their hardiness. Here’s how to grow an endless supply of onions in your garden!
Typically, onions are planted early in the spring and harvested in the fall after their tops begin to die back. In the southern U.S., some onion varieties can be planting in the fall.
We recommend using onion sets, which can be planted without worry of frost damage and have a higher success rate than direct seed or transplants.
Botanical name: Allium cepa
family: Liliaceae
Climate and Soil:
An ideal soil should have pH in between 6.5 to 8. The soil should be well aerated. Heavy soil should be avoided. It is grown under a wide range of climatic conditions. However, it cannot stand too hot or too cold weather. It prefers moderate temperature in summer as well as in winter. Short days are very favorable for the formation of bulbs. It can be grown well at elevations of 1000 to 1300 m above MSL. Onion requires well drained loamy soils, rich in humus, with fairly good content of potash. The crop raised on sandy or loose soil does soils, the bulbs produced are deformed and during harvesting, many bulbs are broken and bruised and so they do not keep well in storage.
Varieties
Pusa Red, Pusa Ratnar, Pusa White Round, Patna Red, Poona Red, Arka Pragati, Arka Niketa, Patna White, Bombay White, Nasik Red.
Planting Habits:
It is grow as an annual or biennial. The smooth, glaucous scope grows from 1 to 3 feet high. The scope or stem is hollow and swollen above the base. The leaves are also swollen at base and hollow. Flowers, terminal, umbel, white or faint blue, numerous, develop bulbels. Underground bulb undeveloped like the stem. Propagation by Bulbels.
Propagation
Onion belong to bulb vegetables group. Onion seeds are sown in nursery from October to November. In south and eastern India from September to October. In hills from March to June. One hectare needs 8-10 kg seeds. Seedlings are transplanted in December and January. Early transplanting yields more. Bulb and bulb-lets are also sown but needs 1000-1200 kg. / hectare.
Planting
The seed of onion in the nursery from middle of October to the end of November. In the hills, the seed is sown from March to June. Planting distance for Onion (seedlings) is 15 X 10 or 20 X 10cm
Manures and Fertilizer
Onion F.Y.M. 200-250 g/hectare
45-65 Kg N/hectare
40-60 kg P/hectare
60-100 kg K/hectare
Irrigation:
Irrigation during growth should be steady and uninterrupted otherwise dryness may cause splitting of the outer scales. Irrigation is stopped when the tops mature and start falling. Use F1 hybrids for higher yield.
Plant Protection
Pest
- Thrips- Spray Malathion or Nuvacron (0.1%)
- Borer- Spray Endosulfan (0.1%)
- Maggot- Apply Thimet 10G to soil and spray Malathion (0.05%)
Diseases
- Downy mildew- Spray Difolatan (0.1%) or Dithane M-45 (0.2%)
- Smut – Spray Captan, Biltox or Thiram 75%
Harvesting
Onion harvesting is done when the still green tops start drooping. The plants are gently pulled out from the soil. However, 10-15 days before harvesting irrigation of the field is stopped. The crop is also sprayed with 1000 ppm carbendazim 30 days before harvest. This helps increase the shelf-life of the crop. The bulbs are cleaned and dried in shade for 4 days.
Yield
Onion gives a yield of 25 to 30 tones/hectare and garlic about 6 to 10 tonnes. Bulbs should be thoroughly cured before storage.
Storage
Generally, onion bulbs harvested in rabi season have better shelf-life than kharif. Light red onion varieties have better storage potential than the dark red varieties. They are stored in jute bags or wooden baskets. They are also stored in netted bags. This is important because onions emit gas which if may lead to rotting if not allowed to escape. Optimum temperature for storage is 30-35˚C with 65-70% relative humidity.
Cold storage increases the shelf life. The loss of crop after storing in cold for six months has been found to be 5%. However, extremely low temperature (less than -2⁰C) can lead to freezing injury. A high temperature can cause rotting. A gradual decrease of temperature prevents microbial decay.
