Allium sphaerocephalon


Allium sphaerocephalon is a plant species in the Amaryllis family known as round-headed leek and also round-headed garlic, ball-head onion, and other variations on these names. Other names include Drumsticks, and in Germany, Kugellauch. Some publications use the alternate spelling A. sphaerocephalum. It is a hardy perennial plant.
Allium sphaerocephalon is found in the wild across all parts of Europe except in the northernmost countries. Its native range extends to northern Africa and to western Asia as far east as Iran. It is also reportedly naturalised in New York State in the US. In the UK it grows wild only in the Avon Gorge so is known locally as the Bristol onion.
The species is prized by gardeners because of its striking floral display. The spherical "head" is borne on a long scape, up to 50 cm in height, usually in July. It can contain hundreds of deep purple flowers.
This plant has gained the Royal Horticultural Society’s Award of Garden Merit.

Description

Allium sphaerocephalon produces egg-shaped bulbs. Small bulblets are present under the outer layer of the stem. Flowers are borne on a scape up to 50 cm in height, in a spherical to egg-shaped umbel, 1–6 cm in diameter, tightly packed with many flowers crowded together. The relatively small size of the umbel relative to the height of the stem makes this one of those described as 'drumstick alliums'. Individual flowers are reddish-purple and are occasionally replaced by bulbils.
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