Back to main Search Page

Allium cepa proliferum - (Moench) Regel.

Tree Onion

Author	(Moench) Regel.	Botanical references	200
Family	Alliaceae	Genus	Allium
Synonyms	Allium cepa viviparum - (Metzg.)Alef. Allium x proliferum - (Moench.)Schrad. ex Willd.
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].
Range	Original habitat is obscure.
Habitat	Not known in the wild.
Edibility Rating	5 (1-5)	Medicinal Rating	3 (1-5)

Physical Characteristics

Bulb growing to 1.2m.

The plant prefers light (sandy) and medium (loamy) soils and requires well-drained soil. The plant prefers acid, neutral and basic (alkaline) soils. It cannot grow in the shade. It requires moist soil.

Habitats

Cultivated Beds;

Cultivars: (as above except)
'Catawissa'
'McCullar's White Topset'
'Moritz Egyptian'
'Norris Egyptian'

Edible Uses

Edible Parts: Leaves; Root.

The plant forms small bulbs at the top of the flowering stem, these can be eaten raw or cooked[16, 33]. They have a strong onion flavour and are often used as pickled onions or added to salads[K]. As long as the bulbils are dried properly at harvest time, they store well[4]. Bulb - raw or cooked. The bulb can be up to 4cm in diameter and has a strong onion flavour[K]. Chopped into slices, it makes a good addition to salads and can also be used as a vegetable or as a flavouring in cooked foods[K]. Leaves - raw or cooked. A strong onion flavour, it makes a nice flavouring in salads though it should not be harvested in quantity because this would reduce the yield of bulbils[K]. The leaves are produced from late autumn, though we have found that harvesting them at this time will often encourage diseases such as mildew[K].

Medicinal Uses

Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.

Anthelmintic; Antiinflammatory; Antiseptic; Antispasmodic; Carminative; Diuretic; Expectorant; Febrifuge; Hypoglycaemic; Hypotensive; Lithontripic; Skin; Stomachic; Tonic.

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, 7, 21]. When used regularly in the diet it offsets tendencies towards angina, arteriosclerosis and heart attack[254]. It is also useful in preventing oral infection and tooth decay[254]. Baked onions can be used as a poultice to remove pus from sores[254]. Fresh onion juice is a very useful first aid treatment for bee and wasp stings, bites, grazes or fungal skin complaints[7, 201]. When warmed the juice can be dropped into the ear to treat earache[254]. 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].

Other Uses

Cosmetic; Dye; Hair; Polish; Repellent; Rust.

The juice of the plant is used as a moth repellent and can also be rubbed onto the skin to repel insects[7]. The plant juice can be used as a rust preventative on metals and as a polish for copper and glass[7]. A yellow-brown dye is obtained from the skins of the bulbs[141, 168]. Onion juice rubbed into the skin is said to promote the growth of hair and to be a remedy for baldness[7]. It is also used as a cosmetic to get rid of freckles[7]. The growing plant is said to repel insects and moles[201]. 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].

Cultivation details

Prefers a sunny position in a light well-drained soil[1] but succeeds in most soils that are in good condition[16]. Tolerates a pH in the range 4.5 to 8.3. The bulbs should be planted fairly deeply[1]. Some modern works have moved this plant from A. cepa, seeing it as being of hybrid origin with A. fistulosum and therefore renaming in A. x proliferum. The tree onion is a genuinely perennial form of A. cepa that is sometimes grown in the herb garden for its edible bulbils. Plants rarely if ever produce seed, instead the flowering head is comprised of a number of small onions or bulbils[16, 33]. Plants are propagated by means of these bulbils or by dividing the main bulb that grows underground[K]. By no means a heavily productive plant, though the bulbils are very well flavoured and the plant is fairly easily grown[K]. Its main problem is that slugs seem to be attracted to it and can eat to death even well-established plants[K]. Grows well with most plants, especially roses, carrots, beet and chamomile, but it inhibits the growth of legumes[18, 20, 54]. This plant is a bad companion for alfalfa, each species negatively affecting the other[201]. Said to be immune to onion root fly[16]. Members of this genus are rarely if ever troubled by browsing deer[233].

Propagation

Harvest bulbils in late summer and replant immediately or store them in a cool dry frost-free place and plant them out in late winter or early spring. Division of the bulbs after the leaves die down in late summer.

Cultivars

'Catawissa'

A very hardy cultivar of Canadian origin, distinguished by its vigorous growth and the rapidity with which the bulbils commence to grow without being detached from the top of the stem[183]. The bulbils divide into tiers, the second set of bulbils producing green shoots, leaves or barren stems to bring the height of the plant to over 75cm[183].

'McCullar's White Topset'

This form produces a number of white bulbs below the ground about 25cm or more in diameter, plus pea-sized bulbils at the top of the flower stalk[183]. The larger bulbs are used for eating, the bulbils are used for replanting[183]. It is used primarily as a source of greens when other onions are dormant[183].

'Moritz Egyptian'

Similar to the typical tree onion, but the bulbs are a deeper colour (red-purple) and the topsets are slightly larger than most strains[183]. An unusual strain that will sometimes produce sets in the middle of the stalk[183].

'Norris Egyptian'

This cultivar is less pungent and more productive than other strains[183].

Links

This plant is also mentioned in the following PFAF articles: Allium Species - the Perennial Onions, The Potted Garden.

References

[K] Ken Fern
Notes from observations, tasting etc at Plants For A Future and on field trips.

[1] F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951
Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaces in 1992 by a new dictionary (see [200]).

[4] Grieve. A Modern Herbal. Penguin 1984 ISBN 0-14-046-440-9
Not so modern (1930's?) but lots of information, mainly temperate plants.

[7] Chiej. R. Encyclopaedia of Medicinal Plants. MacDonald 1984 ISBN 0-356-10541-5
Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.

[16] Simons. New Vegetable Growers Handbook. Penguin 1977 ISBN 0-14-046-050-0
A good guide to growing vegetables in temperate areas, not entirely organic.

[18] Philbrick H. and Gregg R. B. Companion Plants. Watkins 1979
Details of beneficial and antagonistic relationships between neighbouring plants.

[20] Riotte. L. Companion Planting for Successful Gardening. Garden Way, Vermont, USA. 1978 ISBN 0-88266-064-0
Fairly good.

[21] Lust. J. The Herb Book. Bantam books 1983 ISBN 0-553-23827-2
Lots of information tightly crammed into a fairly small book.

[33] Organ. J. Rare Vegetables for Garden and Table. Faber 1960
Unusual vegetables that can be grown outdoors in Britain. A good guide.

[54] Hatfield. A. W. How to Enjoy your Weeds. Frederick Muller Ltd 1977 ISBN 0-584-10141-4
Interesting reading.

[76] Cooper. M. and Johnson. A. Poisonous Plants in Britain and their Effects on Animals and Man. HMSO 1984 ISBN 0112425291
Concentrates mainly on the effects of poisonous plants to livestock.

[141] Carruthers. S. P. (Editor) Alternative Enterprises for Agriculture in the UK. Centre for Agricultural Strategy, Univ. of Reading 1986 ISBN 0704909820
Some suggested alternative commercial crops for Britain. Readable. Produced by a University study group.

[168] Grae. I. Nature's Colors - Dyes from Plants. MacMillan Publishing Co. New York. 1974 ISBN 0-02-544950-8
A very good and readable book on dyeing.

[183] Facciola. S. Cornucopia - A Source Book of Edible Plants. Kampong Publications 1990 ISBN 0-9628087-0-9
Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.

[200] Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992 ISBN 0-333-47494-5
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.

[201] Allardice.P. A - Z of Companion Planting. Cassell Publishers Ltd. 1993 ISBN 0-304-34324-2
A well produced and very readable book.

[233] Thomas. G. S. Perennial Garden Plants J. M. Dent & Sons, London. 1990 ISBN 0 460 86048 8
A concise guide to a wide range of perennials. Lots of cultivation guides, very little on plant uses.

[254] Chevallier. A. The Encyclopedia of Medicinal Plants Dorling Kindersley. London 1996 ISBN 9-780751-303148
An excellent guide to over 500 of the more well known medicinal herbs from around the world.

Readers Comments

Plants for a Future does not verify the accuracy of reader comments, use at your own risk. In particular Plants For A Future can not take any responsibility for any adverse effects from the use of plants. You should always consult a professional before using plants medicinally.

Allium cepa proliferum

keith exelby Wed Jan 31 2007

my father always grew tree-onions [in the 1940s] but I have not been able to buy any seed bulbs can you name a supplier Keith Exelby

Allium cepa proliferum

Ken Fern, Plants for a Future Mon Mar 5 2007

There are a number of suppliers in Britain. For details visit the Plant Finder at http://www.rhs.org.uk/RHSPlantFinder/plantfinder.asp

Allium cepa proliferum

Matt Cavens Sat May 23 2009

If anybody grows or knows a supplier for the "Norris Egyptian" please could they get in touch. I grow the other 3 varieties of this onion and are willing to swap.

Allium cepa proliferum

Jo Blair Mon Sep 14 2009

I am also looking for specific cultivars of allium proliferum as all the companies I have looked at only supply non-named varieties. Anyone got any contacts that would help me? Thanks

Add a comment/link:

Discussion Monitor

To have posts to this page mailed to you enter your email address here:

(Your email address will not appear on the webpage or be passed on to third parties).