Blue globe onion (Allium caeruleum) AL-ee-um sir-EW-lee-um Genus:  Allium This plant produces dense clusters of bright blue flowerheads up to 1 inch wide. Its leaves clasp its stem and die back before flowering. Care:  Provide full sun and well-drained, average to dry soil. Propagation:  Sow seed in spring in containers or in situ. Divide clump-forming plants in spring. Problems:  Bulb rot in damp conditions. Onion fly and thrips.

Overview

Height 1 ft. to 3 ft. Spread 6 in. to 12 in. Growth Habit Clumps Growth Pace Fast Grower Light Full Sun Only Moisture Dry to Medium Maintenance Low Characteristics Showy Flowers, Showy Seed Heads Bloom Time Early Summer, Summer Flower Color Blue Uses Beds and Borders Style Cottage Garden, Meadow Garden, Rock Garden Seasonal Interest Summer Interest Type Bulbs