Onion (Red)

Tamil Name: Vengayam; Scientific Name: Allium cepa;

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Planting/Sowing

Nov – Feb;

Harvesting

Apr – Jul; (following year)

First Harvest

~140 Days

General Info

Crop categoryVegetable, Greens
Life spanBiennial
Type of cropHerb
Part(s) of the crop to harvestRoot, Leaves, Microgreen
Avg. Height6 – 18 inches

Climate & Humidity

Onions need cool and pleasant weather without humidity and rain, so they are best sown in cooler months in tropical regions.

Planting / Sowing

When to plant / sow seeds (ideal season):
November to February;

How to plant:
Direct Sowing and Transplanting: Soak the onion seeds in water for one day. Drain and keep them in the open for the next 2-3 days. Later, sow the seeds in soil on a tray. The seeds usually take 6-8 weeks to sprout and once it does, the saplings need to be transplanted to larger spaces such as grow bags / on the ground.

NOTE: Onion shoots can be used as a flavourful fresh herb. Please refer to the How to Grow Greens and How to Grow Microgreens sections as Onions may also be harvested at the microgreen stage.

Soil Depth & Spacing Requirements

Depth – 1 inch, spacing – 6-8 inches.

NOTE: Please go through the Guides in the Knowledge Base for more details on topics ranging from Spacing & Lighting to Soil and Nutrients.

Irrigation

Water regularly to ensure the soil is moist to facilitate growth.

NOTE: Irrigation should depend on how moist / wet the soil is. Check your plants everyday to see if they require irrigation or not. Check the Watering & Irrigation guide for more info.

Harvesting

When to harvest 
For root: 4-5 months after planting the seeds. You will know that the plant is ready when the tops of onions are visible above the soil.

For greens: Trim tender shoots as required. Greens will keep regrowing.

Microgreens are harvested as seedlings at the 2 leaf stage.

How to harvest
For onion bulbs, once the leaves begin to shrivel, you can pull out the bulbs from the soil.

For greens/microgreens, snip with garden scissors.

NOTE: Harvest periods can vary depending on environmental, climatic, and soil conditions.

Pests & Diseases

PestsThrips, onion maggots
Common Diseases/ ProblemsTo control thrips, take a dark piece of paper into the garden and knock the onion tops against it; if thrips are present, you will spot their tan-colored bodies on the paper.
Pest and Disease prevention measure(s)Read Pest & Disease Control for more info.

NOTE: Read Pest & Disease Control for more information.

Did you know?

Cutting onions cause you to tear up because onion cells release a gas when they are damaged as a defense mechanism. The root portion has the highest concentration, so you may want to avoid cutting that part. Refrigerating onions / dunking them in ice cold water and using a very sharp knife can also reducing tearing. Also, the more onions you cut, the less susceptible you will be to tearing up! [Source]

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