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Allium giganteum

Giant Onion
Allium giganteum
Allium giganteum

One of the tallest ornamental onions, this selection looks beautiful as an accent in garden beds and in fresh or dried arrangements; large globes of small, purple, star shaped flowers stand above low mounded, fragrant green foliage; low maintenance

Ornamental Features

Giant Onion features bold balls of lightly-scented purple flowers at the ends of the stems from early to mid summer. The flowers are excellent for cutting. Its sword-like leaves remain green in color throughout the season.

Planting & Growing

Giant Onion will grow to be about 12 inches tall at maturity extending to 4 feet tall with the flowers, with a spread of 12 inches. It grows at a medium rate, and under ideal conditions can be expected to live for approximately 8 years. As an herbaceous perennial, this plant will usually die back to the crown each winter, and will regrow from the base each spring. Be careful not to disturb the crown in late winter when it may not be readily seen! As this plant tends to go dormant in summer, it is best interplanted with late-season bloomers to hide the dying foliage.

Light Requirement:


Cold Hardy to Zone:



Soil pH:

Soil Type

Fall Color

Deer Resistance:

full sun







12 inches


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