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Useful Temperate Plants

Allium cepa

L.

Amaryllidaceae

+ Synonyms

Allium angolense Baker

Allium aobanum Araki

Allium cepaeum St.-Lag.

Allium commune Noronha

Allium cumaria Buch.-Ham. ex Wall.

Allium esculentum Salisb.

Allium napus Pall. ex Kunth

Allium nigritanum A.Chev.

Allium pauciflorum Willd. ex Ledeb.

Allium salota Dostál

Ascalonicum sativum P.Renault

Cepa alba P.Renault

Cepa esculenta Gray

Cepa pallens P.Renault

Cepa rubra P.Renault

Cepa vulgaris Garsault

Kepa esculenta Raf.

Porrum cepa (L.) Rchb.

Common Name: Onion

No Image.

General Information

Allium cepa is a herbaceous, perennial plant (usually grown as an annual or biennial in cultivation) producing 4 - 10 leaves about 30cm long and a flowering scape that can be up to 100cm tall from an underground bulb. The plant divides, forming in time a cluster of plants[
266
Title
Flora of China
Publication
 
Author
 
Website
http://flora.huh.harvard.edu/china/
Publisher
Missouri Botanical Garden Press; St. Louis.
Year
1994
ISBN
 
Description
An excellent, comprehensive resource in 25 volumes. In addition to the botanical information the flora also gives basic information on habitat and some uses. An on-line version is also available.
].
The onion was one of the first plants to be cultivated for food and medicine[
244
Title
Herbs
Publication
 
Author
Phillips. R. & Foy. N.
Publisher
Pan Books Ltd. London.
Year
1990
ISBN
0-330-30725-8
Description
Deals with all types of herbs including medicinal, culinary, scented and dye plants. Excellent photographs with quite good information on each plant.
]. It is very widely cultivated in most parts of the world for its edible bulb and leaves, there are many named varieties capable of supplying bulbs all the year round[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
]. This is one of the most cultivated plants in the world, widely grown especially for its edible bulb, but also for its leaves.

Known Hazards

There have been cases of poisoning caused by the consumption, in large quantities and by some mammals, of this plant. Dogs seem to be particularly susceptible[
76
Title
Poisonous Plants in Britain and their Effects on Animals and Man.
Publication
 
Author
Cooper. M. and Johnson. A.
Publisher
HMSO
Year
1984
ISBN
0112425291
Description
Concentrates mainly on the effects of poisonous plants to livestock.
].

Botanical References

200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
,
270
Title
Flora of N. America
Publication
 
Author
 
Website
http://flora.huh.harvard.edu/fna/
Publisher
 
Year
0
ISBN
 
Description
An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.

Range

The original habitat is obscure, the plant probably arose in C. Asia (Turkmenistan) - its nearest relative is Allium vavilovii or Allium oschanini

Habitat

Not known in the wild.

Properties

Edibility Rating *  *  *  *  *
Medicinal Rating *  *  *
Other Uses Rating *  *
HabitEvergreen Bulb
Height0.60 m
PollinatorsBees, Insects
Cultivation StatusCultivated

Cultivation Details

Onions are best grown in a Mediterranean climate, the hot dry summers ensuring that the bulbs are ripened fully[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
]. For best growth, however, cool weather is desirable at the early stages of growth[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
]. Plants are frost-tolerant but prolonged temperatures below 10°c cause the bulb to flower[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
]. Optimum growth takes place at temperatures between 20 and 25°c[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
]. Bulb formation takes place in response to long-day conditions[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
].
Prefers a sunny sheltered position in a rich light well-drained soil[
1
Title
RHS Dictionary of Plants plus Supplement. 1956
Publication
 
Author
F. Chittendon.
Publisher
Oxford University Press
Year
1951
ISBN
-
Description
Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [200]).
,
16
Title
New Vegetable Growers Handbook.
Publication
 
Author
Simons.
Publisher
Penguin
Year
1977
ISBN
0-14-046-050-0
Description
A good guide to growing vegetables in temperate areas, not entirely organic.
]. Prefers a pH of at least 6.5[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
]. Plants tolerate a pH in the range of 4.5 to 8.3.
Plants are perennial but the cultivated forms often die after flowering in their second year though they can perennate by means of off-sets[
1
Title
RHS Dictionary of Plants plus Supplement. 1956
Publication
 
Author
F. Chittendon.
Publisher
Oxford University Press
Year
1951
ISBN
-
Description
Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [200]).
].
This species was derived in cultivation from Allium oschaninii[
203
Title
Alliums. The Ornamental Onions.
Publication
 
Author
Davies. D.
Publisher
Batsford
Year
1992
ISBN
0-7134-7030-5
Description
Covers about 200 species of Alliums. A very short section on their uses, good details of their cultivation needs.
]. Most forms are grown mainly for their edible bulbs but a number of varieties, the spring onions and everlasting onions, have been selected for their edible leaves. There are several sub-species:-
Allium cepa 'Perutile' is the everlasting onion with a growth habit similar to chives, it is usually evergreen and can supply fresh leaves all winter.
Allium cepa aggregatum includes the shallot and the potato onion. These are true perennials, the bulb growing at or just below the surface of the ground and increasing by division. Plants can be divided annually when they die down in the summer to provide bulbs for eating and propagation.
Allium cepa proliferum is the tree onion, it produces bulbils instead of flowers in the inflorescence. These bulbils have a nice strong onion flavour and can be used raw, cooked or pickled. Most modern treatments are now referring to this form as Allium x proliferum, being seen as a hybrid with the Welsh Onion (Allium fistulosum).
Onions grow well with most plants, especially roses, carrots, beet and chamomile, but they inhibit the growth of legumes[
18
Title
Companion Plants.
Publication
 
Author
Philbrick H. and Gregg R. B.
Publisher
Watkins
Year
1979
ISBN
-
Description
Details of beneficial and antagonistic relationships between neighbouring plants.
,
20
Title
Companion Planting for Successful Gardening.
Publication
 
Author
Riotte. L.
Publisher
Garden Way, Vermont, USA.
Year
1978
ISBN
0-88266-064-0
Description
Fairly good.
,
54
Title
How to Enjoy your Weeds.
Publication
 
Author
Hatfield. A. W.
Publisher
Frederick Muller Ltd
Year
1977
ISBN
0-584-10141-4
Description
Interesting reading.
,
201
Title
A - Z of Companion Planting.
Publication
 
Author
Allardice.P.
Publisher
Cassell Publishers Ltd.
Year
1993
ISBN
0-304-34324-2
Description
A well produced and very readable book.
]. This plant is a bad companion for alfalfa, each species negatively affecting the other[
201
Title
A - Z of Companion Planting.
Publication
 
Author
Allardice.P.
Publisher
Cassell Publishers Ltd.
Year
1993
ISBN
0-304-34324-2
Description
A well produced and very readable book.
].
Members of this genus are rarely if ever troubled by browsing deer[
233
Title
Perennial Garden Plants
Publication
 
Author
Thomas. G. S.
Publisher
J. M. Dent & Sons, London.
Year
1990
ISBN
0 460 86048 8
Description
A concise guide to a wide range of perennials. Lots of cultivation guides, very little on plant uses.
].

Edible Uses

Bulb - raw or cooked. A very versatile food, the bulb can be 10cm or more in diameter and is widely used in most countries of the world. Eaten raw, it can be sliced up and used in salads, sandwich fillings etc, it can be baked or boiled as a vegetable in its own right and is also commonly used as a flavouring in soups, stews and many other cooked dishes. Some cultivars have been selected for their smaller and often hotter bulbs and these are used for making pickles.

Leaves - raw or cooked[
2
Title
Sturtevant's Edible Plants of the World.
Publication
 
Author
Hedrick. U. P.
Publisher
Dover Publications
Year
1972
ISBN
0-486-20459-6
Description
Lots of entries, quite a lot of information in most entries and references.
,
37
Title
The Gardener's Assistant.
Publication
 
Author
Thompson. B.
Publisher
Blackie and Son.
Year
1878
ISBN
-
Description
Excellent general but extensive guide to gardening practices in the 19th century. A very good section on fruits and vegetables with many little known species.
]. There are some cultivars, the spring onions, that have been selected for their leaves and are used in salads whilst still young and actively growing - the bulb is much smaller than in other cultivars and is usually eaten with the leaves. By successional sowing, they can be available at any time of the year.

Flowers - raw. Used as a garnish on salads. The flowers are somewhat dry and are less pleasant than many other species[
K
Title
Plants for a Future
Author
Ken Fern
Description
Notes from observations, tasting etc at Plants For A Future and on field trips.
].

The seeds are used whole as a spice, especially in Indian cookery[
K
Title
Plants for a Future
Author
Ken Fern
Description
Notes from observations, tasting etc at Plants For A Future and on field trips.
]. They can be sprouted and eaten, and have a delicious onion flavour[
K
Title
Plants for a Future
Author
Ken Fern
Description
Notes from observations, tasting etc at Plants For A Future and on field trips.
].

Medicinal

Although rarely used specifically as a medicinal herb, the onion has a wide range of beneficial actions on the body and when eaten (especially raw) on a regular basis will promote the general health of the body.
The bulb is anthelmintic, anti-inflammatory, antiseptic, antispasmodic, carminative, diuretic, expectorant, febrifuge, hypoglycaemic, hypotensive, lithontripic, stomachic and tonic[
4
Title
A Modern Herbal.
Publication
 
Author
Grieve.
Publisher
Penguin
Year
1984
ISBN
0-14-046-440-9
Description
Not so modern (1930's?) but lots of information, mainly temperate plants.
,
7
Title
Encyclopaedia of Medicinal Plants.
Publication
 
Author
Chiej. R.
Publisher
MacDonald
Year
1984
ISBN
0-356-10541-5
Description
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
,
21
Title
The Herb Book.
Publication
 
Author
Lust. J.
Publisher
Bantam books
Year
1983
ISBN
0-553-23827-2
Description
Lots of information tightly crammed into a fairly small book.
]. When used regularly in the diet it offsets tendencies towards angina, arteriosclerosis and heart attack[
254
Title
The Encyclopedia of Medicinal Plants
Publication
 
Author
Chevallier. A.
Publisher
Dorling Kindersley. London
Year
1996
ISBN
9-780751-303148
Description
An excellent guide to over 500 of the more well known medicinal herbs from around the world.
]. It is also useful in preventing oral infection and tooth decay[
254
Title
The Encyclopedia of Medicinal Plants
Publication
 
Author
Chevallier. A.
Publisher
Dorling Kindersley. London
Year
1996
ISBN
9-780751-303148
Description
An excellent guide to over 500 of the more well known medicinal herbs from around the world.
]. Baked onions can be used as a poultice to remove pus from sores[
254
Title
The Encyclopedia of Medicinal Plants
Publication
 
Author
Chevallier. A.
Publisher
Dorling Kindersley. London
Year
1996
ISBN
9-780751-303148
Description
An excellent guide to over 500 of the more well known medicinal herbs from around the world.
].

Fresh onion juice is a very useful first aid treatment for bee and wasp stings, bites, grazes or fungal skin complaints[
7
Title
Encyclopaedia of Medicinal Plants.
Publication
 
Author
Chiej. R.
Publisher
MacDonald
Year
1984
ISBN
0-356-10541-5
Description
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
,
201
Title
A - Z of Companion Planting.
Publication
 
Author
Allardice.P.
Publisher
Cassell Publishers Ltd.
Year
1993
ISBN
0-304-34324-2
Description
A well produced and very readable book.
]. When warmed the juice can be dropped into the ear to treat earache[
254
Title
The Encyclopedia of Medicinal Plants
Publication
 
Author
Chevallier. A.
Publisher
Dorling Kindersley. London
Year
1996
ISBN
9-780751-303148
Description
An excellent guide to over 500 of the more well known medicinal herbs from around the world.
]. It also aids the formation of scar tissue on wounds, thus speeding up the healing process, and has been used as a cosmetic to remove freckles[
7
Title
Encyclopaedia of Medicinal Plants.
Publication
 
Author
Chiej. R.
Publisher
MacDonald
Year
1984
ISBN
0-356-10541-5
Description
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
].

Bulbs of red cultivars are harvested when mature in the summer and used to make a homeopathic remedy[
232
Title
The Complete Homeopathy Handbook.
Publication
 
Author
Castro. M.
Publisher
Macmillan. London.
Year
1990
ISBN
0-333-55581-3
Description
A concise beginner's guide to the subject. Very readable.
]. This is used particularly in the treatment of people whose symptoms include running eyes and nose[
232
Title
The Complete Homeopathy Handbook.
Publication
 
Author
Castro. M.
Publisher
Macmillan. London.
Year
1990
ISBN
0-333-55581-3
Description
A concise beginner's guide to the subject. Very readable.
].

Agroforestry Uses:

Onions generally grow well with most plants, especially roses, carrots, celery, celariac, beet and chamomile, but they inhibit the growth of legumes[
18
Title
Companion Plants.
Publication
 
Author
Philbrick H. and Gregg R. B.
Publisher
Watkins
Year
1979
ISBN
-
Description
Details of beneficial and antagonistic relationships between neighbouring plants.
,
20
Title
Companion Planting for Successful Gardening.
Publication
 
Author
Riotte. L.
Publisher
Garden Way, Vermont, USA.
Year
1978
ISBN
0-88266-064-0
Description
Fairly good.
,
54
Title
How to Enjoy your Weeds.
Publication
 
Author
Hatfield. A. W.
Publisher
Frederick Muller Ltd
Year
1977
ISBN
0-584-10141-4
Description
Interesting reading.
]. This plant is a bad companion for alfalfa, each species negatively affecting the other[
201
Title
A - Z of Companion Planting.
Publication
 
Author
Allardice.P.
Publisher
Cassell Publishers Ltd.
Year
1993
ISBN
0-304-34324-2
Description
A well produced and very readable book.
].
Members of this genus are rarely if ever troubled by browsing deer[
233
Title
Perennial Garden Plants
Publication
 
Author
Thomas. G. S.
Publisher
J. M. Dent & Sons, London.
Year
1990
ISBN
0 460 86048 8
Description
A concise guide to a wide range of perennials. Lots of cultivation guides, very little on plant uses.
].

Other Uses

The juice of the plant is used as a moth repellent and can also be rubbed onto the skin to repel insects[
7
Title
Encyclopaedia of Medicinal Plants.
Publication
 
Author
Chiej. R.
Publisher
MacDonald
Year
1984
ISBN
0-356-10541-5
Description
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
].

The plant juice can be used as a rust preventative on metals and as a polish for copper and glass[
7
Title
Encyclopaedia of Medicinal Plants.
Publication
 
Author
Chiej. R.
Publisher
MacDonald
Year
1984
ISBN
0-356-10541-5
Description
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
].

A yellow-brown dye is obtained from the skins of the bulbs[
141
Title
Alternative Enterprises for Agriculture in the UK.
Publication
 
Author
Carruthers. S. P. (Editor)
Publisher
Centre for Agricultural Strategy, Univ. of Reading
Year
1986
ISBN
0704909820
Description
Some suggested alternative commercial crops for Britain. Readable. Produced by a University study group.
,
168
Title
Nature's Colors - Dyes from Plants.
Publication
 
Author
Grae. I.
Publisher
MacMillan Publishing Co. New York.
Year
1974
ISBN
0-02-544950-8
Description
A very good and readable book on dyeing.
].

Onion juice rubbed into the skin is said to promote the growth of hair and to be a remedy for baldness[
7
Title
Encyclopaedia of Medicinal Plants.
Publication
 
Author
Chiej. R.
Publisher
MacDonald
Year
1984
ISBN
0-356-10541-5
Description
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
,
254
Title
The Encyclopedia of Medicinal Plants
Publication
 
Author
Chevallier. A.
Publisher
Dorling Kindersley. London
Year
1996
ISBN
9-780751-303148
Description
An excellent guide to over 500 of the more well known medicinal herbs from around the world.
]. It is also used as a cosmetic to get rid of freckles[
7
Title
Encyclopaedia of Medicinal Plants.
Publication
 
Author
Chiej. R.
Publisher
MacDonald
Year
1984
ISBN
0-356-10541-5
Description
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
].

The growing plant is said to repel insects and moles[
201
Title
A - Z of Companion Planting.
Publication
 
Author
Allardice.P.
Publisher
Cassell Publishers Ltd.
Year
1993
ISBN
0-304-34324-2
Description
A well produced and very readable book.
]. A spray made by pouring enough boiling water to cover 1kg of chopped unpeeled onions is said to increase the resistance of other plants to diseases and parasites[
201
Title
A - Z of Companion Planting.
Publication
 
Author
Allardice.P.
Publisher
Cassell Publishers Ltd.
Year
1993
ISBN
0-304-34324-2
Description
A well produced and very readable book.
].

Propagation

Seed. Early sowings can be made in late winter in a greenhouse to be planted out in late spring. The main sowing is made in early spring or mid spring in an outdoor seedbed, this bed must be very well prepared. A sowing can also be made in an outdoor seedbed in August of winter hardy varieties (the Japanese onions are very popular for this). These overwinter and provide an early crop of onion bulbs in early summer of the following year.
Onion sets can be planted in early to mid spring. Sets are produced by sowing seed rather thickly in an outdoor seedbed in late spring or early summer. The soil should not be too rich and the seedlings will not grow very large in their first year. The plants will produce a small bulb about 1 - 2cm in diameter, this is harvested in late summer, stored in a cool frost-free place over winter and then planted out in mid spring. A proportion of the bulbs will run quickly to seed but most should grow on to produce good sized bulbs.
Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2018-12-14. <temperate.theferns.info/plant/Allium+cepa>

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