Alliums are a popular bulb flower known for their giant spherical flower heads that look like colorful fireworks. They come in shades of purple, pink white, yellow and more. Alliums make a big statement in the garden and work beautifully as cut flowers.
If you love the look of alliums but want to expand beyond the typical ornamental onion there are several other flowers that give a similar effect. Keep reading to discover 5 allium look-alikes to grow in your garden.
Globe Thistle
Globe thistle (Echinops ritro) is a clump-forming perennial that produces rounded blue flowering heads the size of a softball. The small florets are densely packed into prickly spheres atop long straight stems, mimicking the form of Allium giganteum.
Though globe thistle looks like an allium, it’s actually a member of the Asteraceae family The flowers make excellent cut or dried flowers. Globe thistle thrives in full sun and well-drained soil. It grows 2-4 feet tall. Zones 3-10
Sea Holly
Sea holly (Eryngium varieties) offers strong steel blue stems and prickly silver bracts encircling true blue conical flower heads. It has an otherworldly, geometric appearance reminiscent of Allium schubertii.
Sea holly is a member of the Apiaceae family along with alliums. It prefers full sun and average to dry soil. Good drainage is key. Sea holly grows 1-3 feet tall depending on variety. Zones 4-9.
Ornamental Onion
Ornamental onion (Tulbaghia violacea) produces rounded umbels of tiny lilac flowers with bright yellow stamens on sturdy stalks. Its blooms look nearly identical to Allium aflatunense.
Despite its common name, ornamental onion is actually in the Amaryllidaceae family. It has attractive gray-green foliage that emits an onion/garlic scent when crushed. Ornamental onion thrives in full sun to part shade and well-drained soil. It grows 1-2 feet tall. Zones 7-10.
Drumstick Allium
Drumstick allium (Allium sphaerocephalon) is often confused with a similar-looking flower called summer hyacinth (Galtonia candicans). Both produce dense egg-shaped flower heads on straight, slender stems.
The main difference is that true drumstick allium has burgundy bloom stalks and leaves that smell like onions when crushed. Summer hyacinth has green bloom stalks and leaves that lack aroma. Summer hyacinth grows a bit taller at 2-3 feet. Both prefer full sun and well-drained soil. Zones 4-9.
Ornamental Onion
Spider flower (Cleome hassleriana) is an annual that offers spherical flower heads with long, spidery stamens that resemble the tentacles of Allium schubertii. The blooms come in shades of white, pink, rose, and purple.
Spider flower thrives in full sun and moist, well-drained soil. It self seeds readily. Spider flower grows 3-5 feet tall. It adds vertical interest to beds and borders. Bees and butterflies love it. Ornamental onion is another non-allium that mimics the look of A. schubertii with its purple ball-shaped blooms. Zones 10-11.
Growing Tips
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Plant bulbs in fall; sow annuals in spring after the last frost.
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Give plants plenty of room to spread. Space 1-3 feet apart depending on mature size.
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Deadhead spent blooms to encourage reblooming. Leave some for seed production.
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Stake tall flowers like sea holly and spider flower to prevent flopping in wind and rain.
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Fertilize bulbs when foliage emerges; feed annuals weekly. Use a balanced fertilizer.
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Mulch beds to help retain moisture and suppress weeds. Replenish mulch in spring.
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Water during drought, soaking the soil thoroughly vs frequent light watering.
Companion Plants
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Grasses like miscanthus, pennisetum, stipa
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Other daisy flowers: coneflower, black-eyed Susan, shasta daisy
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Bee balm, catmint, gayfeather
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Ornamental herbs: lavender, sage, thyme
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Late spring bulbs: tulips, daffodils, hyacinths
Design Uses
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Group in drifts of 3, 5, or 7 for maximum impact.
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Mix heights for dimension and structure.
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Mass behind shorter border plants.
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Line a pathway or edge beds and borders.
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Plant in rows or blocks in a cutting garden.
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Use as thriller plants in containers.
Attracting Pollinators
Globe thistle, sea holly, ornamental onions, and spider flower are excellent for attracting bees, butterflies, and other beneficial pollinators to your garden. Their nectar-rich blooms provide food for pollinators while their pollen supplies protein. Planting in drifts offers insects a convenient buffet.
By including allium look-alikes and other pollinator-friendly flowers in your garden, you create an essential habitat for bees, butterflies, and hummingbirds where they can feed, nest, and thrive all season long.
Easy-Care Alternatives
Alliums offer gorgeous architectural form but their blooms are fleeting. If you love the look but want longer lasting flowers, consider these easy-care alternatives:
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Yarrow – ferny foliage, flat-topped blooms in white, yellow, pink. Thrives in heat and drought.
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Liatris – vertical spikes of fluffy purple blooms. Attracts butterflies. Deer resistant.
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Salvia – long blooming with spires of blue, violet, red or white flowers. Heat and drought tolerant.
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Veronica – spiky blue, pink or white flower spikes. Withstands wind, rain, and humidity.
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Sedum – fleshy leaves, dense flower umbels in autumn. Drought and pest resistant.
Enjoy AlliumLook-Alikes
Add intrigue to your garden by incorporating flowers that mimic the unique shape and form of ornamental alliums. Their eye-catching spheres and umbels attract attention while providing food and habitat for pollinators. Blend classic allium bulbs with perennial and annual look-alikes for stunning floral displays all season long.
Can alliums be grown from seed?
You can grow them from seeds, but hybrids won’t grow. It could take a year or more for them to bloom.
Learn more about planting and caring for flower bulbs.
During the growing season, provide alliums with evenly moist, but not soggy, soil. Cut back watering in the dormant season when too much water can cause rot.
Add bone meal to the planting area at the time of planting. In following years, add a layer of compost to keep soil healthy.
Don’t cut off the foliage while it’s still green; let it die back naturally. This feeds the bulbs and sets them up for a good flower show next year. To avoid seeing fading bulb foliage, plant among perennials that require similar conditions.
Although their stems are strong, taller varieties should be staked if planted in windy areas.
Alliums are virtually pest-free and will even repel garden pests such as aphids. However, thrips can be problematic occasionally. Additionally, they bring in good bugs like bees, parasitic mini wasps, and hoverflies that help control bug pests.
Are alliums deer resistant?
Close cousins to onions and garlic, deer are deterred by their scent.
Allium caeruleum bulbs. Photo by: Max_555 / Shutterstock
Plant in fall, a few weeks before the ground freezes.
Plant allium bulbs twice as deep as the bulb is tall, with the pointy end up.
Generally tolerant of soil type; the important thing to remember is they must have well-drained soil. Avoid wet locations, especially during their dormant period, which can lead to rotting.
An Amazing Summer Bloomer! ‘Serendipity’ Allium
FAQ
What plants are similar to alliums?
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