The potato onion (also known as an Egyptian onion, underground onion or multiplier onion) is a group of varieties
from ''Plants For A Future'' which

Maud Grieve file:Maud Grieve in 1928 (cropped).png, Maud Grieve in 1928 Sophie Emma Magdalene Grieve (née Law; 4 May 1858 – 21 December 1941), also known as Maud, Margaret, Maude or Mrs. Grieve, was the principal and founder of The Whins Medicinal and ...

calls ''Allium'' × ''proliferum'' but has also been classed in the Aggregatum Group of ''Allium cepa'', similar to the

shallot The shallot is a cultivar group of the onion. Until 2010, the (French red) shallot was classified as a separate species, ''Allium ascalonicum''. The taxon was synonymized with '' Allium cepa'' (the common onion) in 2010, as the difference was t ...

. It sometimes produces irregular-shaped or round

bulb In botany, a bulb is a short underground stem with fleshy leaves or leaf basesBell, A.D. 1997. ''Plant form: an illustrated guide to flowering plant morphology''. Oxford University Press, Oxford, U.K. that function as food storage organs duri ...

s, which in some old English varieties may be large, although others may be less so. According the French ethnobotanist Michel Chauvet, the potato onion, also called family onion, forms several more or less flattened bulbs which, unlike shallots, remain enveloped in external

tunics A tunic is a clothing, garment for the torso, usually simple in style, reaching from the shoulders to a length somewhere between the hips and the ankles. It might have arm-sleeves, either short or full-length. Most forms have no fastenings. The ...

. The term ''aggregatum'' was coined to describe this type. It is cultivated in the gardens of many countries, including

Finland Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

Sri Lanka Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

, and

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

.Michel Chauvet ''Encyclopedia of food plants'' ''700 species from around the world'', 1700 drawings Belin 2010 878 p39; It is planted from bulbs, not from seed. It should be planted in the fall to early spring. Sources differ about planting depth, some saying shallow planting is appropriate and others calling for deeper planting.

References

External links

Onion cultivars Perennial vegetables {{vegetable-stub