Allium Giganteum: How to Grow, Cut and Gift the Giant Ornamental Onion

Allium giganteum is the giant ornamental onion: a bulb from Central Asia that sends up a bare stem 1.2 to 1.8 metres tall topped with a dense purple-lilac sphere about 10 to 15 cm across. It flowers in late spring and early summer, is planted as a bulb in autumn, and also works beautifully as a long-lasting cut flower and dried decoration.

Below we go through everything a florist would tell you about it: where it comes from, how to grow it, how to make the cut stems last, what the flower is said to mean and how to use it in a gift. If you are sending flowers to someone in Russia, you will also find practical notes on choosing a bouquet and arranging delivery with us.

What Allium giganteum is and how to recognise it

Allium giganteum belongs to the same genus as garlic, leeks and chives, which is why a cut stem has a faint oniony scent when you trim it. The wild plant grows on rocky slopes in the mountains of Central Asia, from northern Iran and Afghanistan into Turkmenistan and Tajikistan. Gardeners value it for one thing above all: height combined with a perfectly round flower head that seems to float above the border.

Each globe is made of hundreds of small star-shaped florets packed on short stalks. Colour ranges from deep violet to soft lilac depending on the strain and light. The leaves are broad, grey-green and strap-like; they appear in early spring and usually start to yellow just as the flowers open, which is normal and not a sign of disease.

People often confuse it with similar large alliums such as 'Globemaster', 'Gladiator' or 'Ambassador'. Those hybrids have comparable globes, but the true species is typically the tallest, with the smallest head relative to its stem, giving it that distinctive drumstick silhouette.

Planting and growing giant alliums

Plant the bulbs in autumn, from September to November in most temperate climates, before the ground freezes. Set them about 15 to 20 cm deep, roughly three times the height of the bulb, and 25 to 30 cm apart. Groups of three, five or seven look far more natural than a single stem.

Full sun and very well-drained soil matter more than rich feeding. Alliums rot in heavy, waterlogged clay, so add grit or plant on a slope if your ground stays wet in winter. The species is hardy to around minus 25 C, so it survives most Russian and northern European winters in the ground, especially under a light mulch.

Because the foliage fades early, plant giant alliums behind perennials that fill out in June: catmint, hardy geraniums, peonies or ornamental grasses hide the yellowing leaves while the purple globes stand clear above them. Leave the leaves until they are fully brown so the bulb can store energy for next year.

A common disappointment is a bulb that produces leaves but no flower. The usual causes are too much shade, bulbs planted too shallow, or a small, underweight bulb in its first year. Buy large, firm bulbs, plant them deep enough and give them a sunny spot, and they will keep flowering for many years. Every few years you can lift crowded clumps in summer after the leaves die back and replant the offsets.

Bouquets we can deliver

Bouquet of 1 yellow sunflowers

$13

Bouquet of 3 white French roses with eucalyptus, 50 cm

$18

Bouquet of 3 red French roses with eucalyptus, 50 cm

$18

Bouquet of 3 pink roses with eucalyptus, 50 cm

$18

Using Allium giganteum as a cut flower

Cut stems when about a third of the florets in the globe have opened; the rest will open in the vase over the following days. Cut early in the morning, re-cut the base at an angle under water, and stand the stems in deep, cool water for a few hours before arranging.

A giant allium can last ten days to two weeks in a vase, which is longer than most summer flowers. The onion smell comes only from the sap at the cut end. Changing the water every day or two and rinsing the vase keeps it unnoticeable. A drop of flower food or a few drops of bleach in the water also helps keep bacteria down.

Because the stems are tall and the heads heavy, use a tall vase with a narrow neck or a weighted container. In mixed bouquets the globes work as a focal point with peonies, delphiniums, eremurus and large garden roses, or on their own in a minimalist arrangement of three to five stems.

If you receive alliums in a bouquet, take off any packaging, trim 2 to 3 cm from each stem with a sharp knife and put them straight into cool water. Keep the vase away from radiators, direct sun and the fruit bowl, because ripening fruit releases ethylene that shortens the life of most cut flowers.

Drying alliums and using seed heads

After flowering the globe turns into a sphere of green and then straw-coloured seed capsules. Many gardeners leave these standing in the border right through autumn because they keep their shape and catch frost beautifully.

To dry them for the house, cut the heads once the colour has faded and hang them upside down in a dry, dark, airy room for two to three weeks. The dried spheres can be left natural, used in wreaths and winter arrangements or lightly sprayed with paint for a festive look. Keep dried heads away from damp rooms, where they quickly lose their shape.

Meaning of the allium flower and when to give it

In the language of flowers alliums are associated with unity, patience and good fortune. The idea comes from the shape: hundreds of small flowers bound into one perfect sphere. That makes a giant allium a thoughtful choice for a wedding, an anniversary, a housewarming or a new business.

There is no traditional taboo around alliums in Russian flower etiquette, so they are safe to give. The usual Russian rule still applies to the bouquet as a whole: for happy occasions give an odd number of stems, because even numbers are reserved for funerals and remembrance. Three or five giant alliums in a tall arrangement follow that rule naturally.

Alliums suit people who like modern, architectural flowers rather than classic romantic bouquets. For a more traditional recipient, combine one or two globes with roses or peonies so the bouquet feels both striking and familiar.

Sending flowers with alliums to Russia

Giant alliums are a seasonal cut flower, at their best in late spring and early summer, so whether they can go into a bouquet depends on the time of year. The easiest way is to browse our bouquets catalogue and then message a manager on WhatsApp to ask what can be put together for your date. The manager can help you choose, agree the time, address and card text, and send a photo of the bouquet before delivery.

We deliver across Russia. City delivery costs 500 RUB; for remote districts and suburbs the operator confirms the price when confirming the order. In large cities express delivery takes 1 to 2 hours after the order is confirmed. You can also choose an exact time (plus or minus 30 minutes), a window of 09-12, 12-15, 15-18 or 18-21, or pre-order 1 to 30 days ahead, which is handy for birthdays and anniversaries.

Delivery is anonymous by default, so the courier does not name the sender unless you write your name on the card; the card itself is free. The courier calls the recipient about 15 minutes before arrival. If nobody is home, we agree a second delivery the same day or leave the flowers with a neighbour or concierge with your consent. You pay online by bank card, SBP or Yandex Pay; all details are on the delivery and payment page.