Plant of the Month for May: Allium 'Globemaster'

Beautiful big drumsticks of purple – now there’s something to catch your eye in the garden. Alliums (ornamental onions) make a great choice to brighten up our gardens in late spring and provide striking architectural interest.

Our Hyde Hall Plant of the Month is Allium ‘Globemaster’. Why? Because it has very stout, sturdy stems and very large spherical deep purple flower heads made up of hundreds of small star-shaped flowers that last for weeks.  The best bit is the way they create a dramatic effect as their heads appear to ‘bob’ among the surrounding planting.

In this garden, we all believe alliums are best planted in large drifts among our permanent plantings. As the flowers fade the large round seedheads continue to add interest until early summer (and the other plants will hide the fading foliage). Over time, alliums will slowly bulk up and set seed, and as they do so the naturalistic drift will change over time, creating a dynamic planting.

At Hyde Hall we use alliums extensively and you can find Allium ‘Globemaster’ in the Dry Garden (left) where it enjoys the open, sunny conditions on the south facing slope. We manage the Dry Garden naturalistically and the alliums blend into this style of planting very well as they weave their way between the permanent planting.

If starting a garden from scratch we’d recommend complementing Allium ‘Globemaster’ with late spring favourites such as Euphorbia characias subsp. wulfenii ‘Lambrook Gold’ and Helleborus argutifolius because they give striking contrasts with their lime green flowers. (And, oh, look – this is what we have in the Dry Garden at Hyde Hall). As we move into early summer consider partnering them with plants such as Salvia nemorosa ‘Caradonna’ or Astrantia ‘Hadspen Blood’ which will give a softer colour combination with their dark purple to claret flowers.

Alliums are extremely easy to maintain. Plant in autumn 5-10cm (2-4in) deep in a sunny in well-drained soil and remove the seed heads and foliage only once they die back.

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