Use alliums to bridge the June gap between the flowers of spring and the summer flowering perennials. Even when your garden borders are bright with colour in June from Euphorbias, Geums and Iris there is still a role for alliums. Their round pompom flower heads are larger than tennis balls and contrast boldly both in colour and form with everything around them.
Tulips, daffodils and shrubs such as Deutzias fill my garden in spring, but in mid June the Phlox, Monardas, Geraniums and Nepeta are not quite yet in flower and that is where ornamental onions can play their part.
I try new ones each year alongside the stalwarts such as Allium ‘Purple Sensation’, A. ‘Ambassador’ and tall white A. ‘Mount Everest’. Additionally, Allium cristophii (or do you prefer A. christophii’?) is indispensable with its wide, airy, flowering globes held just 50 cm above ground level. These nestle perfectly amongst freshly emerging grasses and perennials from early June onwards.
My latest discoveries are Allium ‘Powder Puff’ and ‘Violet Queen’. Unlike the others they seem to throw up two or even three flowers per bulb and I have been struggling to tell the difference between them. One is said to have a smaller and less rounded flower head which may be true, but this simply means that there is a subtle variation of flowers when they are mixed together. This suggests natural variation which fits well into my style of naturalistic meadow planting.
I had always thought of Allium atropurpureum as simply a dark flowered version of A. nigrum; which in spite of its name is white. It is not. Allium atropurpueum starts flowering a couple of weeks later when all the others are fading. Its heads are not quite as large, but more compact and a deep rich shade of maroon/purple. Being held high it rises clearly above surrounding perennials and if planted in bold patches will make a very effective focal point in a mixed border. Next year I will be planting it generously around the clumps of Calamagrostis brachytricha in the border shown here.