Blue Globe Onion Allium caeruleum

The blue globe onion  is a perennial bulb from the amaryllis family (Amaryllidaceae). The bulb, native to Central Asia and northeastern China, is found in dry slopes, steppes and plains in these regions. The species epithet is Latin for "dark blue" in reference to its showy blue flowers.

The bulb grows easily in humus-rich, well-drained, moist to dry loams in full sun. It does best in dry conditions, as bulbs may rot in excessively moist soil. Blue flowers form in 1-inch clusters atop 1- to 2-foot stiff stems, May through June. Leaves on the lower stem often disappear by blooming time. The Blue Globe Onion spreads by bulblets and self-seeding but is not considered aggressive. Plant bulbs four to six inches deep or divide established plants in the fall for spring blooms. 

A beautiful globe-shaped flower head aloft a tall, elegant stem makes this plant a striking addition to any garden. Flower heads remain upright long after the blooms have faded and create sculptural interest. These showy bulbs received the Royal Horticultural Society Award of Garden Merit. 

Bulbs can be used in perennial beds, rock gardens, meadows, cottage garden and naturalized areas. They can be planted in clusters or within a perennial bed for a special pop of color. They are considered a good cutting flower, attract butterflies, and are deer resistant.

Insects, Diseases, and Other Plant Problems:  There are no serious insect or disease problems. May be susceptible to downy mildew. It is considered mildly toxic

VIDEO Created by Laura Barth for "Vegetables, Herbs, Fruits, and Nuts," a plant identification course developed in partnership with Longwood Gardens.

More information on Allium.