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ALLIUM CRISTOPHII

These stylish alliums have enormous spherical flower heads comprising individual purple stars. Flowering from June into July, the flowers can reach 20cm (8in) in diameter and have a metallic sheen. Strappy grey green foliage can start to look tatty, but don’t cut it back too soon – hide it with herbaceous perennials such as geraniums and save the flower heads for structure in late summer. H60cm (24in) S20cm (8in)