The majestic and stunning Giganteum allium is perhaps the tallest available allium on the market, with blooms the size of a softball, it grows up to 5 feet tall. Giganteum is a fall planted flower bulb that blooms from late spring into early summer. Like all alliums, Giganteum is best planted in clumps of 10 or more bulbs to create a stunning and unusual effect in the late spring garden. Giganteum alliums should be planted in a sheltered location to protect the blooms from strong winds. Giganteum allium is excellent for either cut flower or dried flower arrangements.