Alliums can thrive in either full or partial shade, however full sun is preferred.
The bulbs are typically winter-hardy in hardiness zones 3–8. See this USDA Hardiness Zone Map to determine your growing zone.
Alliums require well-drained soil that does not become wet in order to be cultivated, just like the majority of other bulbs.
Where to Plant Alliums
Most alliums bloom in late spring, right after the last tulips and before irises and peonies, in perennial gardens. The flowers last for weeks and give the garden a balloon-like appearance as they float above it. After flowering, the foliage and flowers disappear, making space for summer perennials to take the lead. Allium christophii, Gladiator, Globemaster, Purple Sensation, and more excellent alliums for perennial gardens include these.
Alliums do well in rock gardens, where they flourish in the well-drained crevices between the boulders. Select species with smaller leaves, such as Allium sikkimense, Allium flavum, and Allium karataviense.
Alliums make great cut flowers, according to cutting gardens. The flowers remain a very long time and are easy to arrange thanks to their rigid stalks. You may guarantee that you’ll always have an abundant supply of flowers for bouquets by planting alliums in a cutting garden. You’ll receive flowers all season long if you select a variety. Purple Sensation, Allium atropurpureum, Mount Everest, Allium sphaerocephalon, and Allium tuberosum are all good choices.
Containers: Whether grown alone or in combination with other plants, many alliums thrive in containers. When the flowers blossom, you can relocate the planter to a visible location so that you can enjoy the flowers.
How to Plant Alliums
When to Plant: Bulbs-based alliums are planted in the fall, just after the first frost and before the ground freezes. Like other perennials, herbaceous alliums (such as Allium tuberosum and Allium millenium) have fibrous roots. You can plant these at any point of the growing season.
Planting Depth and Spacing: Planting depth is based on bulb size. Smaller bulbs, such drumstick alliums, should only be planted 3 deep in comparison to larger bulbs like Globemaster, which should be planted 5 to 6 deep. Follow the plant-specific directions on the packaging or on our website for the best results.
Planting advice: You don’t have to be concerned about deer, squirrels, or voles when growing alliums. Allium bulbs have an onion-like flavor that repulses them, and they almost invariably leave them alone.
Can I still plant allium bulbs?
Or perhaps you didn’t get a chance to visit the garden center this fall and are concerned that come spring your landscape will be drab, monochromatic, and devoid of lovely tulips, crocus, daffodils, and allium! We’re happy to inform you. Bulbs can be planted at any time.
What season should you plant allium bulbs?
Most likely, when you think of alliums, you picture those plants with the traditional round, purple flowerheads on long stalks that make borders look amazing in late spring and early summer. Alliums, however, are much more than this.
There are alliums that are white, pink, blue, and yellow. There are some alliums that resemble a fireworks display, and others that resemble knotted dreadlocks.
You can identify that alliums are related to onions, garlic, and leeks by the aroma released when you crush the foliage. This family also includes chives (Allium schoenoprasum), which have delicious leaves that may be sliced and used to salads and dips.
Alliums are a favorite of butterflies and bees, and even the dried flowerheads look lovely in the border or in floral arrangements.
When to plant allium bulbs
The greatest time to plant alliums is in mid- to late-autumn, at the same time as tulips and daffodils that bloom in the spring. Allium bulbs are resilient and can withstand harsh winter weather if they are planted in soil that drains effectively.
Some attractive alliums, like “Allium sphaerocephalon,” flower in the late summer. Most ornamental alliums bloom in the late spring and early summer.
Where to plant alliums
The majority of alliums thrive in full sun and well-drained soil. Tall alliums should be planted in a protected area to prevent the stems from blowing over in high winds. Plant purple-flowered chives (‘Allium schoenoprasum’), which appreciate afternoon shade, or yellow-flowered ‘Allium moly’ in shaded areas.
Tall alliums look great planted in broad swaths or punctuated across a border. Late-summer bloomer Allium sphaerocephalon has gorgeous wine-red flowers that stand out amid the grasses in prairie planting schemes.
Long, slender leaves on ornamental alliums fade back as the flowers emerge. To conceal the waning foliage, place allium bulbs under other low-growing plants.
Planting allium bulbs
- Remove any weeds by turning the dirt over. Dig in leaf mold or compost instead of using manure on heavy soil as this can change the soil’s pH level. Alliums thrive in soil with a pH that is neutral.
- Make a hole that is roughly four times the bulb’s depth.
- Put a bulb in the opening with the roots pointing down.
- Gently compact the earth after filling the hole.
Alliums can also be grown in large pots with soil that is a mixture of grit, John Innes No. 3 compost, and multipurpose compost.
Tips on caring for alliums
- Ground-planted alliums typically don’t require irrigation.
- In the spring, alliums grown in containers will require regular watering. However, avoid letting the compost become soggy as this could lead to the bulbs rotting.
- Crushed eggshells around plants, copper tape around pots, beer traps, or wildlife-friendly slug pellets can all be used to deter slugs and snails from eating new spring leaves.
- When the plants are in bloom, spread a general-purpose fertilizer to aid in the development of the bulbs, assuring healthy flowers the following year.
- Once the leaves have withered back, remove them.
- There is no need to deadhead the flowerheads unless you choose to because they still look excellent after flowering has completed. As long as they remain in place at the border, they may be ignored.
- Put pots in a greenhouse or up against a wall of a house in the winter to shield them from the cold weather.
Growing allium bulbs from offsets
Offsets, which are little bulbs affixed to the main bulb, are produced by many allium bulbs. These can either be planted directly in the ground or split from the main bulb and placed in tiny pots to grow on. Before they have developed enough to produce flowers, it will take a number of years.
Wait until the allium plants are through flowering before using a garden fork to carefully uproot the plants and inspect the bulbs for offsets. Replant the bulbs after removing any offsets.
Best allium bulbs to plant
Alliums come in a wide variety, from large to little, with flowerheads that are rounded or exotic-looking twisted. Here is a selection of the most well-liked alliums.
- One of the most well-known alliums, Allium ‘Purple Sensation’ has the traditional deep purple spherical flowerheads on long, robust stalks. 1 m (3.5 ft) high.
- Large circular purple flowerheads up to 15 cm (6 in) across on robust stems that are 80 cm (3 ft) tall characterize Allium ‘Globemaster’.
- As its name suggests, Allium giganteum is a true giant with dense, spherical purple flowerheads on stems up to 1.8 meters (6 feet) tall.
Should you soak allium bulbs before planting?
For example, Allium Giganteum (Giant Allium) frequently has a bulb that is 2-3 inches long “tall. Then, place this bulb between 6 and 9 “deep within the earth. “Pointy end” up when planting bulbs Once all the bulbs have been planted, thoroughly wet the area.
ALLIUM PLANTING GUIDE
The allium family includes the chives in your herb garden, which are little, fluffy purple balls that bees and butterflies adore. Alliums used as ornaments, however, are anything but tiny. Big drama is what these enormous globes on tall stems are all about in your landscape. Alliums are a great choice if you are growing bulbs with kids since they enjoy the fact that when these blooms bloom, they frequently tower over them.
Garden & Container Planting
Alliums require a cold spell to establish their roots and get ready for spring, just like other flower bulbs do. So it’s time to start planting as soon as the first chill of fall appears in the air.
Although flower bulbs are hardy and simple to grow, they detest getting their feet wet since they can quickly decay if left to “bathe” in water. Therefore, avoid at all costs moist soil. this refers to locations where puddles are still visible 5–6 hours after a downpour. You can also improve possibly wet soil by incorporating organic material like peat, bark, or manure. The same motto applies when planting bulbs in containers: drainage, drainage, and more drainage. Purchase a container that has at least a few drainage holes at the bottom.
Because alliums require a lot of light to flourish, locations with less than full sun are not suitable.
Alliums must be buried deeply enough so that changes in the temperature above ground—either too warm or too cold—won’t influence them. Because containers can’t protect bulbs as well as mother earth can, it may be preferable to let your containers spend the winter indoors in a cool, dark, well-ventilated area where the temperature won’t rise above 60 degrees Fahrenheit, such as an unheated basement or garage, if you live in one of the hardiness zones 3 to 7.
The bulb is placed at the bottom of the hole with its sharp end facing up, and a hole three times as deep as the bulb’s height is dug to determine the optimal depth. When competing for nutrients with other bulbs, alliums perform worse, therefore it’s best to space them 6 to 8 inches apart.
After planting, it’s crucial to give the bulbs plenty of water to help them settle and develop roots rapidly, but after that, you won’t need to water them again. All that’s left to do is wait patiently for spring to come and surprise you with the fruits of your labor and for winter to work its magic underground.
Alliums don’t typically need watering during the flowering season, but you can water them if there hasn’t been any rain for three to five days.
Don’t trim the foliage of alliums right away after they have stopped flowering; through photosynthesis, the leaves will produce the nutrition the bulb needs for its subsequent growing season. The leaves will naturally turn yellow and die back after a few weeks, at which point you can remove it. The bulb will now enter dormancy and won’t require watering again until the following spring.
How to plant alliums in your garden:
- Wait till the soil is 60°F or colder before planting. This will happen around September or October in the North and October or November in the South.
- Choose a location in your garden that has soil that drains properly and receives full sun.
- The allium bulbs should be planted with their pointed ends facing up, 4 to 8 inches deep, and 6 to 8 inches apart.
- once, and then wait until spring.
- Don’t remove the leaf from alliums after they bloom. Remove it once it has entirely withered and become yellow.
How to plant alliums in containers:
- Wait until the soil temperature is at least 60 degrees Fahrenheit and the weather is chilly. This will happen around September or October in the North and October or November in the South.
- Choose a location in your garden that receives direct sun.
- Find a container with good drainage, fill it with loose soil, and make sure that water won’t collect and pool at the bottom.
- The allium bulbs should be buried in the ground with their pointed ends facing up, 4 to 8 inches deep, and 6 to 8 inches apart. You can try putting the bulbs closer together since containers frequently have a small amount of room, but make sure they never touch.
- If you reside in hardiness zones 3–7, you can water well once and wait until spring, or you can bring the containers inside and let them spend the winter in a cool place like an unheated garage or basement.
Special effects
You can choose the extremely regulated technique if you prefer order and cleanliness or if you want to maximize the wow-factor alliums can provide to your garden or container. Grow your alliums in straight rows with roughly 10 bulbs spaced closely apart (you might want to add some fertilizer to the soil to make sure they still get all the nutrients they need). Growing a row of 10 taller alliums, like Purple Sensation, behind a row of 10 slightly shorter ones, like Azureum, can produce an even more dramatic effect.
Allium bulbs can be planted in the winter.
If Spring is still in bloom where you live, it’s probably not too late to plant your allium bulbs!
Allium bulbs can be planted in the spring, but fall-planted bulbs will put on a spectacular display the following year.
Allium bulbs can be added to your garden whenever the soil is suitable for planting and you can dig a hole deep enough.
Having said that, blooms planted in the fall will perform best in their first year. First-year flowers from spring-planted bulbs may be sparse, unlikely to blossom, and less vigorous than those from fall-planted bulbs. Or, plants might not blossom until the end of summer or the beginning of fall.
It’s not too late if you didn’t have time to plant those bulbs in the autumn.
Allium bulbs can be planted in the fall and spring, but you should avoid doing so in the early winter. Bulbs planted in the early winter won’t have enough time to take root properly and could perish when the ground freezes.
how do you dry alliums?
Pick off seedheads that are starting to fade and store them for a few months in a cold, dry place, such a shed or cellar. To use as Christmas decorations, I like to dry my seedheads and then spray-paint them silver.
are alliums edible?
Since they are all members of the allium family, onions, leeks, and garlic are often consumed foods. Alliums are theoretically edible, but beware eating any that are designed to be aesthetic garden plants because they may have been chemically treated.
are alliums good for bees?
In the spring, bees and other pollinators are all over our alliums. Our neighborhood beekeeper also claims that the honey doesn’t taste oniony.
do alliums need staking?
Even the tallest alliums won’t need staking since their sturdy stems can hold them if they are planted deeply enough in full sun (so they don’t extend toward the light) and in a sheltered location (so they don’t blow over in the wind).