Allium sphaerocephalon - Roundheaded Garlic
Better known as the drumstick allium, as the flowerheads are egg-shaped, not round, Allium sphaerocephalon is a medium-sized, bulbous perennial with an upright, rather architectural habit, ideal for the middle of a border. The grassy, mid-green leaves wither before the plant flowers, so plant behind a low-growing perennial, Stipa tenuissima grass or silvery Artemisia Powis Castle, for example. From July to August, egg-shaped green flowers, 1”/2.5cm tall, turn rich maroon-red, starting at the top of the flower, and are highly attractive to bees and other pollinators. Seeds about mildly. It makes a lovely cut flower, but put a drop of bleach in the water to minimise the oniony smell. Divide bulbs only if flowering diminishes. Round-headed garlic is an easy, trouble-free plant, and holds the RHS Award of Garden Merit.
Site: Sheltered
Soil: Any well-drained soil; tolerates heavier soils than most alliums
Position: Full sun
Season of interest: Summer
Hardiness: Very hardy
Height: up to 3’ (90cm) Spread: 3” (8cm)