Onion
Allium cepa
Also known as
Garden Onion, Shallot, Bulb onion, Common onion
Photo by Going.Local (All rights reserved)
Full Sun
Easy care
Moderate watering
Frost Hardy
H7-H4
RHS hardiness
-20°C
Minimum temperature
Expected size
Height | Spread | |
---|---|---|
60cm | Max | 20cm |
30cm | Min | 10cm |
2 years to reach maturity
Flowering
-
spring
-
summer
-
autumn
-
winter
This plant has a strong fragrance
More images of Onion
Onion Overview
The Common Onion is grown as an annual but will actually live for 2 years and produce a large pompom-like flower which can have some ornamental value in a cottage garden display. Also grown for the bulb, which is eaten as a vegetable for over 4000 years. It can be used raw in sandwiches and salads as well as being added to many different types of cooked dish.
Common problems with Onion
Onion Companion Plants
How to harvest Onion
When the tops turn yellow and "wilt", it is time to harvest; usually between 100 and 120 days after planting. Gently lift the bulbs before the foliage has fully died back, place the whole plant on racks with good ventilation in full sun to dry out for 2 weeks before being stored in a cool dry location.
How to propagate Onion
Bulbs
Plant onion sets 10cm from mid-March to mid-April. Plant the bulb in the soil with just the tip showing, and firm the soil around them. Birds can be a problem, pulling new sets from the ground so cover with a fleece until firmly rooted.
Seed
Direct sowing in late autumn in a well-prepared bed and thin out later. Will require about 9 to 12 hours of daylight to stimulate bulb formation.
Special features of Onion
Repels harmful insects
The juice is used as a moth repellent. Rubbed into the skin it acts as an insect repellant.
Attracts bees
Only when in flower which is in its second year of growth.
Crop rotation
Onions are light feeders. Plant these after heavy feeders. Follow these crops with legumes.
Other uses of Onion
Culinary, vegetable. Can be grown in containers.
Medicinal
When eaten raw, onions benefit the health in many ways, i.a. anti-inflammatory, antiseptic, prevents tooth decay. The juice is a first-aid treatment for bee stings and quickens healing of wounds.
Edible
Although the bulbs are probably the base ingredient of the vast majority of cooked dishes the world over, the flowers are also edible.
Poisonous to Pets
If your pet likes to nibble your plants, check our collection to make sure what they're eating isn't doing them any harm.
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