Onions are one of the most profitable vegetable crops for farmers due to their high market demand and good storage life.
Proper management from land preparation to post-harvest handling is essential for achieving high yields and quality bulbs.

Select well-drained, fertile sandy loam or loam soils with a pH of 6.0–7.0.

Clear all weeds, crop residues, and stones.

Plough the land deeply (20–30 cm) and harrow until a fine seedbed is obtained.

Prepare raised beds where drainage is poor to prevent waterlogging.
Popular onion varieties include:

Red Creole

Bombay Red

Texas Grano

Red Pinoy

Tropicana F1

Safari F1

Red Coach F1
Choose varieties based on market demand, climate suitability, and disease resistance.

Nursery:
*Sow seeds in a nursery bed.
Transplant seedlings when they are 15–20 cm tall (6–8 weeks old).

Spacing:
30 cm between rows.
10 cm between plants.
This gives adequate space for bulb development and air circulation.
4. FERTILIZER REQUIREMENTS
Before planting:

Apply well-decomposed manure (5–10 tons per hectare).
Basal Fertilizer:

Compound D or NPK (10:20:10 or equivalent)
Top Dressing:

Urea or CAN
100–150 kg/ha split into two applications.
Important:

Avoid excessive nitrogen after bulb formation as it delays maturity and reduces storage quality.
5. MAJOR PESTS AND CONTROL

Thrips
Silvery patches on leaves.
Leaf curling and reduced bulb size.
Control:

Remove weeds.

Avoid overcrowding.

Spray:
Abamectin
Emamectin Benzoate
Spinosad
Lambda-cyhalothrin

Cutworms
Cut young seedlings at ground level.
Control:

Field sanitation.

Deep ploughing.

Spray:
Cypermethrin
Lambda-cyhalothrin

Onion Maggot
Larvae feed on roots and bulbs causing wilting.
Control:

Crop rotation.

Destroy infected plants.

Use recommended soil insecticides.
6. COMMON DISEASES AND MANAGEMENT

Purple Blotch
Purple lesions on leaves.
Management:

Good spacing.

Avoid overhead irrigation.

Spray:
Mancozeb
Chlorothalonil
Azoxystrobin

Downy Mildew
Pale green patches and grey fungal growth.
Management:

Improve air circulation.

Avoid excessive moisture.

Spray:
Metalaxyl + Mancozeb
Copper-based fungicides

Fusarium Basal Rot
Yellowing leaves and rotting bulb base.
Management:

Crop rotation.

Use disease-free seed.

Improve drainage.

Neck Rot
Bulb rotting during storage.
Management:

Proper curing before storage.

Avoid bulb injuries during harvesting.

Water regularly during vegetative growth.

Reduce watering when bulbs begin maturing.

Stop irrigation 10–14 days before harvest to improve bulb quality and storage life.

Harvest when 50–80% of tops have naturally fallen over.

Carefully lift bulbs to avoid bruising.

Remove excess soil but do not wash bulbs.

Dry onions under shade for 2–3 weeks.

Allow necks and outer scales to dry completely.

Remove damaged, diseased, and undersized bulbs.

Store in a cool, dry, well-ventilated place.

Use mesh bags, crates, or racks to allow airflow.
Properly cured onions can be stored for several months with minimal losses.

Successful onion production depends on proper land preparation, balanced fertilization, timely pest and disease control, and careful post-harvest management. Following these practices can significantly increase yields, quality, and profitability.