What's new

Welcome to oiudd | Welcome My Forum

Join us now to get access to all our features. Once registered and logged in, you will be able to create topics, post replies to existing threads, give reputation to your fellow members, get your own private messenger, and so, so much more. It's also quick and totally free, so what are you waiting for?

Posers in Purple: All about Alliums


Staff member
Mar 21, 2024
Reaction score
Posers in Purple: All about Alliums

Arguably the most exciting time of the year for gardeners, May is a month of newly energised plant life. Deciduous trees are a shade of spring green that almost glows in the sunlight, herbaceous perennials are blossoming and the danger of damaging frosts has almost passed. Chelsea Flower Show is also on the horizon. Running this year from 21-25th May, it’s the most significant event in the gardening year and the shows at Tatton Park and Hampton Court are spectacular too. Often featured at all three are alliums, with their eye-catching, purple-headed, pompom-like flowers that appear every year but are always somehow surprising.

The globe-like flowerheads and straight stems of these bold-looking plants add both pops of colour and architectural interest to beds and borders and their form complements other, contrasting flower shapes. Most bloom in shades of purple, mauve and lilac but their range also includes white, pink, blue and even yellow. A hit with bees as well as some butterflies and other pollinators, their seedheads are decorative too, either left in the garden to be touched by frost or in a vase indoors.

Mostly blooming in May and June, ornamental alliums are close relatives of onions, leeks, chives and garlic and the massed, frothy white flowers of wild garlic can also be seen in full bloom in May in wild hedgerows and the dappled shade of woodland. Most ornamental types need good drainage and full sun to really thrive, although one or two will tolerate dappled shade. Their foliage is not their strong point – it has a habit of becoming a little tired and bedraggled-looking, sometimes before the flowers appear. So it’s a good idea to hide this shortcoming by mingling them with other plants.

Plant at least five if budget and space allow. Alliums are happiest in a gang, either as one group intermingled with other plants or as pops of colour dotted around the garden. They suit a range of planting styles from cottage gardens and prairie planting to formal parterres and knot gardens.

Ten alliums for beds and borders

Alliums come in many sizes. Some are tall – up to a metre or more – while tiny A. oreophilum reaches only an undemanding 15cm in height. The flowerheads vary dramatically too, the largest measuring a gaze-seizing 18-20cm in diameter.

Allium siculum
(formerly Nectoroscordum siculum)

Delightful, hanging cream flowers, green-tinted at the base and painted with splashes of burgundy. This stately plant is a veteran, dating back to the 19th century. Happy in sun or part-shade, it’s a valuable addition to the garden. Height and spread approximately 1.2m x 10cm.

Allium ‘Globemaster’

No shrinking violet, this allium produces huge flowerheads growing to 15-20cm in diameter. The colour of blackcurrant ice cream, they have open, star-shaped flowers. Height and spread 1m x 50cm.

Allium ‘Mars’

Compact royal purple flowerheads top this less flamboyant but nevertheless high impact plant. Height and spread 1m x 30cm.

Allium stipitatum ‘Mount Everest’

Another midsummer bloomer, this is a stunning white form with large flowerheads reaching 10-15cm in diameter. Height and spread 1m x 20cm.

Allium sphaerocephalon

One of the most popular species, blooming in mid to late summer. Smallish drumstick-shaped flowerheads emerge bright green, gradually maturing to burgundy from the top downwards, creating an intriguing two tone effect. 90 x 10cm.

Allium hollandicum ‘Purple Sensation’

Smaller and rather more discreet but still an eye-catching addition to the garden with rich violet flowers. Height and spread 80 x 30cm.

Allium cristophii

Large, round, distinctive heads of open, lilac, almost metallic star-shaped flowers, this is another understandably popular variety. Ideal for interplanting with low-growing geraniums. 60 x 20cm.

Allium cernuum

This rather sweet and unusual-looking allium has small, pinkish lilac, hanging, bell-shaped flowers in midsummer. 50 x 10cm.

Allium unifolium

With pale mauve pink long-lasting flowers, this low-growing form will add colour to the front of borders and path edges. 30 x 10cm.

Allium oreophilum

A charming dwarf allium with cerise to pink flowers. Try planting it in gravel with creeping thyme and other alpines. 15 x 10cm.

And a mention too for Allium schoenoprasum, better known as chives, whose pale mauve flowers add early pzazz to the herb patch. Finely chop the leaves and sprinkle them raw over steamed new potatoes, omelettes, fish, summer soups and anything else that takes your fancy. The flowers are edible too (as are the flowers of wild garlic) and add a stylish finishing touch to an early summer salad.


Alliums have many fine qualities and one of the advantages of those with flowers in shades of purple is that they look good with most other colours. They’re particularly striking with white, lime green and orange for a zingy, uplifting vibe, darker burgundies and pinks for a more subtle palette, or white and palest pink to create an ethereal feel.

Plant them with other sun-lovers. Try ever-reliable and versatile hardy geraniums, bright osteospermums, pale candytuft, orange geums, charming Mexican daisy Erigeron karvinskianus, magenta or white Silene coronaria, aromatic nepeta, indigo salvias and rainbow-coloured lupins. It’s good to have a foil for all that colour too so consider lime-green euphorbias, silver stachys and artemesia and grasses like hardy pennisetum, Stipa tenuissima and Carex oshimensis.

We may not have all the plants listed here in our stores, but do talk to our staff, who’ll be happy to help with alternatives.

Planting tips:

  • Place larger alliums at the back of the border or in the middle, where the flower heads will pop up among slightly lower-growing plants.

  • It’s sometimes tempting to buy everything at once. But mixing alliums with plants which bloom before them in spring and after them in summer will mean beds and borders are full of colour for months on end.

  • If you’re surrounding them with other plants to disguise the foliage, consider the height of your alliums’ flowerheads and take this into account when choosing companion plants.

  • Beware exposed, windy areas in the garden. Alliums’ stems, although they often look sturdy, don’t stand up well to buffeting.

Monty Don shows you how to plant them here: https://www.bbc.co.uk/programmes/p05jw2n7

And you can find more advice from a Chelsea grower here: https://www.rhs.org.uk/shows-events/virtual-chelsea/get-out-and-garden/warmenhoven


Alliums need very little maintenance. Deadhead after flowering by chopping off at the base of the stem or leave for eye-catching seedheads over winter. Allow the foliage to die down naturally – it’s next year’s food.

Springing up above more lowly plants in joyful bursts of colour, alliums are the show-offs and stars of the early summer garden. Easy to grow, they’re good for wildlife too, providing food for pollinators and helping to create a healthy garden ecosystem. So, in planting them, you’re doing both yourself and nature a favour.

The post Posers in Purple: All about Alliums appeared first on Capital Gardens.
Top Bottom