Welcome to the diverse world of flowering alliums, a plant family of perhaps four hundred species that includes the familiar onion, garlic, and chives. Planting alliums for their flowers is not a new idea. By Elizabethan times, the giant purple onion was featured as an ornamental garden cover crop. Ornamental alliums bloom in yellow, white, beige, purple, pink and blue. Bloom times vary from spring to fall depending on the species.
Two of the largest and most spectacular alliums bloom in June and make excellent fresh and dried cut flowers. Star of Persia is perhaps the most spectacular. Up to 80, star-shaped flowers are carried in open eight-inch flower clusters. When in bloom, the flowers resemble a lavender to lilac-colored burst of fireworks.
Turkestan alliums are known for their round, dense, three-to-five-inch flower clusters in colors that vary from beige, to pink, to reddish-lilac. Their large flowers on short stems contrast well with their broad, bluish-green leaves.
For the rock garden, try Ostrowsky onion. In June, up to five stems with bright, carmine pink flowers appear only four inches above the ground.
Golden garlic and lily leek are more subtle. Their bright yellow flowers in open clusters on ten-inch stems add a delicate touch to June gardens.
Fall is the best time to purchase and plant these versatile ornamental plant bulbs for blooms next year. Many local garden centers and nurseries stock a variety of alliums.
For more information, see the following Colorado State Extension fact sheet(s).
Do you have a question? Try Ask an Expert!
Updated Friday, April 19, 2013