This popular ornamental onion is native to central Asia, from the Caspian Sea to NW China and SW Siberia. The grass-like leaves may reach 30 cm or more but are mostly withered before the flowers open. The flowers are held on stems 45-60 cm tall. Each stem is topped with a dense, globular, 3 cm diameter head of blue, star-like flowers.
May-June, but as late as July in more northern areas.
Any well-drained soil in full sun will suit this easy-to-please ornamental onion. In autumn, plant the bulbs 5 cm apart, 10 cm deep. For best effect plant them in groups of 10-15. Hardy to zone 4-8.
Bulbs are often available at local nurseries or on-line through bulb nurseries. Mature clumps may be dug and divided once the foliage has dried off. Seeds may also be sown in the fall, with germination in the spring (stratification required).