Allium is a large genus of about 1,100 bulb-forming perennials, mostly from the Northern Hemisphere, including onion, garlic, leek, chives and shallots. Most grow best in full sun with well-drained soil and a cool to moderate climate.
Family
Amaryllidaceae (Daffodil & onion family)
Grows as
Bulb
Light
Full sun
Water
Water regularly during active growth, letting the top layer of soil dry out between waterings to avoid rot.
Soil
Well-drained, fertile soil or loose potting mix.
Temperature
10–25 °C; most species tolerate frost, but bulbs are damaged by prolonged heat above about 30 °C.
How easy
Easy
Safety
Not known to be toxic
Edible
Yes, some parts
About
Allium is a large genus of monocotyledonous flowering plants with 1112 accepted species, making Allium the largest genus in the family Amaryllidaceae and among the largest plant genera in the world. Many of the species are edible, and some have a long history of cultivation and human consumption such as the onion, garlic, scallions, shallots, leeks, and chives.
Allium species occur in temperate climates of the Northern Hemisphere, except for a few species occurring in Chile (such as A. juncifolium), Brazil (A. sellovianum), and tropical Africa (A. spathaceum). They vary in height between 5–150 centimetres (2–59 in). The flowers form an umbel at the top of a leafless stalk. The bulbs vary in size between species, from small (around 2–3 mm in diameter) to rather large (8–10 cm). Some species (such as Welsh onion A. fistulosum and leeks (A.
How to grow it
Many Allium species have been harvested through human history, but only about a dozen are still economically important today as crops or garden vegetables.
Safety
Dogs and cats are very susceptible to poisoning after the consumption of certain species. Cattle have occasionally suffered onion toxicosis as well. There are concerns about Allium consumption by people with G6PD deficiency, a genetic disorder that renders red blood cells highly susceptible to oxidative insult.
The suspected toxic substance in Allium are the sulfur-containing chemicals, specifically disulfides and S-methylcysteine sulfoxide (SMCO): ironically the same ones associated with alleged health benefits in humans and rodents.
Where it grows
The majority of Allium species are native to the Northern Hemisphere, being spread throughout the holarctic region, from dry subtropics to the boreal zone, predominantly in Asia. Of the latter, 138 species occur in China, about a sixth of all Allium species, representing five subgenera. A few species are native to Africa and Central and South America. A single known exception, Allium dregeanum occurs in the Southern Hemisphere (South Africa). There are two centres of diversity, a major one from the Mediterranean Basin to Central Asia and Pakistan, while a minor one is found in western North America. The genus is especially diverse in the eastern Mediterranean.
Uses
The genus includes many economically important species. These include onions (A. cepa), French shallots (A. oschaninii), leeks (A. ampeloprasum), garlic (A. sativum), and herbs such as scallions (various Allium species) and chives (A. schoenoprasum). Some have been used as traditional medicines.
Text excerpted from the Wikipedia article Allium by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.
The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.