Common Name: ornamental onion
Type: Bulb
Family: Amaryllidaceae
Zone: 4 to 8
Height: 1.00 to 1.75 feet
Spread: 1.00 to 1.50 feet
Bloom Time: July to August
Bloom Description: Purple
Sun: Full sun to part shade
Water: Dry to medium
Maintenance: Low
Flower: Showy, Good Cut
Attracts: Butterflies
Tolerate: Rabbit, Deer, Drought, Dry Soil
Culture
Easily grown in average, dry to medium moisture, well-drained soils in full sun to part shade. Best in full sun, but appreciates some light afternoon shade in hot summer climates. Tolerates a wide range of soils. Performs well in sandy soils. Add compost to clay soils, as needed, to improve drainage. Bulbs are best planted in fall. Deadhead after blooming to discourage unwanted seeding in the garden. Divide in the spring or early fall.
Noteworthy Characteristics
The genus Allium contains over 700 species of bulbous or rhizomatous plants. All possess oniony smelling flowers and foliage. Some species are grown for culinary purposes and others for ornamental purposes. Plants typically produce showy flower umbels on naked scapes rising above a clump of linear grass-like leaves. Ornamental alliums generally range in height from 3” to 4-6’ tall.
Genus name comes from the classical Latin name for garlic.
'Serendipity' features blue-tinged foliage and was discovered as a sport of the hybrid ornamental onion Allium 'Millenium'. Globe-shaped inflorescences of purple flowers reaching 1.5-2" in diameter are held above the foliage on sturdy stems in mid to late summer. The flowers are suitable for fresh cut arrangements. Mature clumps will reach up to 1.75' tall and 1.5' wide.
Problems
Bulb rot may occur in overly moist soils. Watch for mildew, rust and leaf spots. Thrips are an occasional problem. Deer and rabbits tend to avoid this plant.
Uses
A striking accent for mixed borders and cottage gardens.