Allium Firmament Ornamental Onion Bulbs

Plant Allium Firmament ornamental onion bulbs before the first frost in fall, and early the next summer, they bloom in baseball-sized flower heads dense with dark silvery-purple florets atop tall scapes rising 24 to 36 inches above a basal rosette of strappy leaves. A favorite of gardeners and pollinators alike, including bees and butterflies, the fragrant flowers are long-lived, staying beautiful in garden for several weeks and remaining attractive even after the flowers fade and the flower heads go to seed. These beautiful blooms make excellent cut flowers, fresh or dried.

An Allium giganteum species, commonly called ornamental onion or giant onion, Firmament is a bulbous perennial with an upright habit and one of the tallest of the ornamental onions. Alliums are in the same family as many edible plants, including garlic, onions, chives, and shallots; but ornamental alliums add an architectural element to the garden with their rounded pompom blooms. Mass plantings of alliums are the most impressive, naturalized in the lawn or ribboned through a mixed bed or border. But they grow well in deep patio pots too and are a great option for a layered lasagna bulb planting with grape hyacinths and anemones.

Ornamental onions are easy to grow. Plant Firmament allium bulbs 8 inches apart and 6 to 8 inches deep an water well to settle bulbs. Once growth begins, feed bulbs with a well-balanced fertilizer. Site in a sunny sheltered location with average, medium moist, freely draining soil. Alliums are not picky about soil type, but soggy soils will cause bulbs to rot. If overcrowding becomes a problem and flower production decreases, dig, divide, and replant the bulbs. Deer and rodents tend to leave ornamental onions alone.

Visit our Bulb Supplies page to find all the tools and materials you need to successfully plant and maintain your bulb plants.

Note: Cannot be shipped to ID, NV, NC, and OR.