It’s unusual on this page to recommend an entire group of plants, but in my travels throughout gardens in the past few years I’ve noticed a rather glaring lack of a particular favorite – Allium. Am I not looking closely enough, or has the genus fallen out of favor?
Once considered a requirement in the cottage garden, it seems Allium has taken a bit of a back seat to other flowering bulbs and perennials, but there is such a tempting variety of selections within the genus that the plants can find a comfortable home in nearly any design. Ranging in size from diminutive to stately and in color from the palest white and pink to blue and brazen purple, this versatile bulb can stand alone or serve as a suitable companion.
We’re all familiar with A. giganteum, among the largest of the group. At nearly 5 feet tall with a massive, softball-sized, purple bloom, it can dominate or serve as a punctuation point. It surely is a conversation starter during spring, and it’s a rather popular choice when you’re looking for a bit of drama. But why stop there?
Common name: Ornamental onion, ornamental garlic
Hardiness: Zones 3(4) to 10
Mature height: 2 to 3+ feet; may reach up to 5 feet
Mature spread: Up to 2 feet
Landscape use: Cottage gardens, mixed borders, containers; taller varieties make the perfect exclamation point in any setting
Ornamental characteristics: Slender to broad straplike leaves that emerge in a subtle rosette form; each straight, leafless stalk supports a round bloom composed of hundreds of florets; some nodding varieties produce flower umbels that droop and dance like bells
One of my favorites is the low-growing A. karataviense, a squat little plant that reaches only about 12 inches tall including the dusky pink flower head, which can develop to about 6 inches in diameter. I plant these at the front of my garden among the deep-purple hued Heuchera, and neighbors (who often forget they’ve already asked) inquire each spring about those unusual flowers.
To the side of the house and intermingled among some evergreens, I have a stand of the unique A. nectaroscordum siculum, whose flowers emerge long and sharply pointed, wrapped in tissue-paperlike protection, which then peels to release an umbel of elegant, bell-shaped, nodding flowers atop very strong but slender, 3-foot-tall stalks. Once the flower matures, the individual floret stalks straighten up again and stand erect to dry.
Alliums of all types can be planted in small groups or in mass for a succession of bloom from May through August, and some continue into October. Dried flower heads of many varieties are just as ornamental as the richly colored fresh blooms, and may be left to highlight the late-fall and winter seasons. For the most part, they’re tough as nails and suffer few diseases, although basal rot and downy mildew can overtake them. They’re highly resistant to deer browsing, however, and because of the sometimes strong onion/garlic scent released by crushed tissue, rodents avoid them.
On the other hand, the flowers of most Allium are attractive to bees and butterflies, making them a welcome addition to a pollinator-friendly garden.
Planted in well-drained soil in full sun, Allium will emerge and return for years to come. Several varieties produce bulblets that will help the plants spread, but few are considered aggressive.
Maybe we didn’t forget about Allium; I certainly hope not. They’re easy to care for and fit nearly anywhere. And with such a wide variety of sizes and colors, there’s no excuse for ignoring them.