Allium Globemaster, commonly called Giant Onion, is perhaps the tallest of the ornamental onions. It is a bulbous perennial (large bulbs to 2-3” diameter) which produces a basal rosette of grayish-green, strap-shaped leaves (to 18” long). From the center of each basal rosette rises a thick, naked, 3-4’ tall scape (stem) which is topped in late spring by a dense, globular, softball-sized, 5-6” diameter cluster (umbel) of tiny, star-shaped, lilac-purple florets.
How to grow
Easily grown in average, medium, well-drained soils in full sun. Best sited in locations sheltered from strong winds. Plant bulbs 5-6” deep and 9-12” apart in fall. Leaves will wither and disappear from the garden shortly after bloom. Mature bulbs may be dug up in the fall, divided and replanted to increase size of a planting.
Zone : 5 to 8
Height : 3 to 4 feet
Spread : 1 to 1.5 feet
Bloom time : May
Bloom description : Deep lavender
Sun : Full sun
Water : Dry to medium
Maintenance : Low
Suggested use : Naturalize
Flower : Showy
Leaf : Fragrant
Attracts : Butterflies
Tolerate : Deer, Drought