Among the largest blooms of the genus, Allium christophii features star-shaped purple-violet flowers with a metallic sheen on loose umbels from 4 to 8 inches across on 1' to 2' plants. Found in nature from Iran and Turkey through Central Asia, and commonly called Star of Persia, this is another of the large-flowered onions that succeed best in Chicago landscapes if interplanted with low-growing perennials and shrubs that will keep soil moisture levels lower during mid to late summer; otherwise, the bulbs have a tendency to rot.

Ornamental onions and edible onions are closely related. The edible onions sold in the supermarket are all a year old; if held in the garden for a second year, they produce large white flowers, but this comes at the expense of the bulb.

The genus name traces its roots to the Latin allium, a name given to garlic and the Celtic adjective for all things hot.