Allium Bulbs

Q: Allium Bulbs Species & Styles?

Popular allium species include Gladiator and Giganteum : these are formidable flowers in terms of size alone, with their flower heads growing 10-25cm across! Similarly, the well-named Mount Everest is one of the taller allium species at an average of 90cm tall. Thinking about mixing and contrasting colours? The more popular varieties are iris purple, but there are plenty of others: the aforementioned ‘Mount Everest’ breed, as well as the smaller Graceful’ Beauty breed, both have a pale silver-lilac colouration. The later-blooming Allium atropurpureum and Allium sphaerocephalon have smaller, denser flower heads that bloom in a richer magenta (and the latter is accented with green). Bright orange and yellow plants lend themselves to an eye-catching, summery effect. For a softer look, try a pale white or pink plant, or a plant with silver foliage.

Creating the most magnificent display, Alliums come in all sorts of shapes and sizes. Although a firm favourite with avid gardeners, these are most popular with bees, butterflies and insects who cannot resist those nectar-rich flowers. Gigantic alliums such as Giganteum will create drama planted in borders, whilst Wild Garlic will fill the air with its scent after those early spring showers.

Like everything we supply here at Boston Seeds, we pride ourselves on supplying professional quality - and for flower bulbs, that means BIG! Our bigger bulbs produce bigger, better and bolder flowers. Choose from our exciting range of varieties - allium surprise bulb collection, old favourites, garden classics as well as striking new lines for 2026.

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Why Grow Allium Bulbs

If you’ll pardon the pun, this bulb flower has a real way of growing on you; it produces medium-to-tall upright stalks ending in a bold globe of fluffy-looking florets in a rich violet colour (though several species have lighter lilac petals). These punchy, purple pom-poms have a real way of drawing the eye - as such, you’re best scattering them evenly throughout a sunny border or a tall, grassy meadow. They’re also excellent cut flowers!

How to grow Allium Bulbs

Allium bulbs are best planted early-to-mid autumn, and typically flower from May to June. They require well-drained soil and plenty of sunlight - be wary of cold or wet conditions where the bulbs may rot.

Their tall, upright stems also require protection from the wind.

Smaller species of allium bulbs should be planted tip up, roughly 10cm apart.

Taller species require 20cm between each bulb.

Ideal planting depth for Allium bulbs is 3 times the bulb height and alternatively, they can be planted in containers.

Alliums are tolerant to drought, prefering a sunnier aspect, and dislike being watered in the summer. Alliums grown in containers will need regular watering, but take care that they don’t get too damp.

Aliums have sparse foliage at the base that will begin to die at flowering time. You can cover these up with lower-growing flowers, or remove them to no ill effect.

Allium Bulbs Species & Styles?

Popular allium species include Gladiator and Giganteum: these are formidable flowers in terms of size alone, with their flower heads growing 10-25cm across! Similarly, the well-named Mount Everest is one of the taller allium species at an average of 90cm tall.

Thinking about mixing and contrasting colours? The more popular varieties are iris purple, but there are plenty of others: the aforementioned ‘Mount Everest’ breed, as well as the smaller Graceful’ Beauty breed, both have a pale silver-lilac colouration. The later-blooming Allium atropurpureum and Allium sphaerocephalon have smaller, denser flower heads that bloom in a richer magenta (and the latter is accented with green).

Bright orange and yellow plants lend themselves to an eye-catching, summery effect. For a softer look, try a pale white or pink plant, or a plant with silver foliage.

Fun Facts About Allium Bulbs

The ornamental allium symbolises unity and patience. Fitting, as it grows dozens of florets in one bulb. In fact, the word “onion” is derived from the latin word unio, as in union!

There aren’t many myths surrounding onions, as you may expect from a plant most commonly seen in the kitchen; however, there are some myths linking them to the magic of tears and the importance of emotional release.

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