Strongly architectural allium stipitatum 39mount everest39 produces perfect globes of up to 50 star45shaped white flowers on tall slender stems flowering from late spring to early summer this ornamental onion is perfect for bridging the gap between spring bulbs and summer bedding plants allium bulbs look spectacular planted in groups where the flowers appear to hover above the border the nectar45rich blooms are also attractive to pollinating insects height 12m 403941