Lilies are a perennial favorite in the garden because of their hardiness, long bloom time, beautiful flowers and fragrant scent. Lilies are members of the genus Lilium. According to the North American Lily Society, lilies are categorized in nine horticultural divisions: Asiatic hybrids; martagon hybrids; candidum hybrids; American hybrids; longiflorum hybrids; trumpet and Aurelian hybrids; Oriental hybrids; interdivisional hybrids; and species lilies. Many of the most popular lilies belong to the Asiatic, Oriental and trumpet lily categories.
Asiatic lilies are hardy in United States Department of Agriculture (USDA) zones 4 through 8. They are early-blooming hybrids, available in many colors and varieties. One of the most popular Asiatic lilies is the tiger lily (Lilium lancifolium.) As the name implies, the showy blossoms are orange and black. The lily grows from 3 to 5 feet tall. The Morning Star lily (Lilium concolor) comes in several varieties, including the coridon, which has wide tepals and is yellow with brown spots, and the reddish-orange pulchellum.
Oriental lilies are hardy to USDA zones 4 through 8. The Maiden Lily from Japan (Lilium rubellum) is also known as Otome-Yuri. It is most often chosen for its pure pink color. Sometimes called the "Queen of Lilies" and known as Yama-Yuri in its native Japan, Lilium auratum have been used to develop many other varieties of Oriental lilies. Platyphyllum lilies (Lilium auratum variety) are a hardy, golden-colored flower that has also been used to develop other varieties, including "Empress of India." Hardy in USDA zones 3 through 9, Black Beauty is a cross between Lilium henryi and Lilium speciosum.
Trumpet lilies are hardy to USDA zones 5 through 9. One exception is the fragrant Black Dragon lily (Lilium leucanthum centifolium), which is hardy from USDA zones 5 through 10. Black Dragons are white with pale yellow centers. Beaverton Pentimento ( a hybrid of Lillium henryi) is a golden lily that was developed near Beaverton, Oregon. It is also hardy to USDA zones 5 through 10.
Lilies in Name Only
Several flowers are commonly referred to as lilies but don't belong to the lilium family. These include the white calla lily (Zantedeschia aethiopica) and the canna lilies or cannas (Canna x generalis.) White calla lilies are a smaller plant, usually just 4 to 6 inches long, while the canna lilies can grow to 5 feet tall. Cannas come in red, pink, yellow and red with yellow. Calla lilies and canna lilies are hardy in USDA zones 8 through 10. Daylilies (Hemerocallis) only bloom for one day, but many plants will produce multiple flowers. They are hardy in USDA zones 3 through 10, depending on the type of daylily.