Allium giganteum, the Giant Onion, is a member of the Alliaceae family that is currently adorning the Hayrick Border in the Parks. It makes a fantastic addition to any border. The flower heads reach around 10cm across and bob in the wind on stems up to 1.5 metres above the ground. The plant flowers through June and July; the foliage dies back quite quickly to leave the flower stems showing.
The Giant Onion prefers full sun, but can also be grown in partial shade. A well-drained soil is important though – if the soil is too wet, try mixing in a good quantity of grit when planting. Planting in a sheltered spot will allow the heads to move in the wind, but if the site is too exposed to strong winds, the stems will snap. Try growing the plant through ornamental grasses to provide additional interest as the grasses are growing. It can be grown from seed or from bulb off-sets in autumn. For more information, visit the RHS website.