Allium giganteum

Giant onion
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Monocots
Order:	Asparagales
Family:	Amaryllidaceae
Subfamily:	Allioideae
Genus:	Allium
Subgenus:	Allium subg. Melanocrommyum
Species:	A. giganteum
Binomial name
Allium giganteum Regel[1]
Synonyms[2][3]
Allium procerum Trautv. ex Regel

Allium giganteum, common name giant onion or giant leek, is an Asian species of onion, native to central and southwestern Asia but cultivated in many countries as a flowering garden plant.[4][5] It is the tallest species of Allium in common cultivation, growing to 1.5 metres (4.9 ft).[6]

In early to midsummer, small globes of intense purple umbels appear, followed by attractive fruiting umbels. A popular cultivar, 'Globemaster', is shorter (80 centimetres (31 in)) but produces much larger, deep violet, umbels (15–20 centimetres (5.9–7.9 in)). Both varieties have been granted the Royal Horticultural Society's Award of Garden Merit.[7][8][9]

In nature, the species is found in Iran, Afghanistan, Turkmenistan, Tajikistan, and Uzbekistan.[3] In cultivation in the US, it performs well in USDA hardiness zones 6–10.[10]

Eating flowers, seeds, leaves, and stems can cause nausea, vomiting, and diarrhea due to the sulfides they contain.[11]

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  Flower opening

References

1. Eduard August von Regel. 1883. Gartenflora 32: 91.
2. The Plant List
3. Kew World Checklist of Selected Plant Families
4. Regel, Eduard August von 1883. Gartenflora (1883) 32: 91
5. Tropicos, Allium giganteum Regel
6. Missouri Botanical Garden: Allium giganteum
7. "Allium giganteum Royal Horticultural Society". Archived from the original on 2014-03-26. Retrieved 2012-06-13.
8. "Allium 'Globemaster' Royal Horticultural Society". Archived from the original on 2014-03-26. Retrieved 2012-06-13.
9. "Allium giganteum". Plants for a Future.
10. "Allium giganteum (Ornamental Onion)". Gardenia.net. Retrieved 2021-07-09.
11. "Allium giganteum (Giant Ornamental Onion, Ornamental Onion) | North Carolina Extension Gardener Plant Toolbox". plants.ces.ncsu.edu. Retrieved 2021-07-09.