Culture
Grow in average, medium moisture, slightly acidic, well-drained soils in full sun to part shade. Prefers rich organic loams. Best sited with the upper parts of the plant in full sun and the roots in shade. Mulch around plants to keep root zones cool. Plant bulbs 4-6” deep in fall. Potted plants may be planted any time from spring to fall. Bulbs need good moisture year-round. Do not allow soil to dry out. Remove flowers as they fade to reduce the setting of seed. After bloom, cut plants back only after leaves and stems turn yellow. Bulbs are rhizomatous.
Noteworthy Characteristics
Lilium formosanum, commonly called Formosa lily, is a Division IX species lily that is native to Taiwan (formerly known as Formosa). It typically grows from 4 to 7 feet tall and features a late summer to fall bloom of pendant, 6-tepaled, sweetly fragrant, trumpet-shaped flowers (to 8-12” long) that are pure white but sometimes tinged with reddish purple on the outside. Each bulb typically produces 2-3 stiff stems clad with lance-shaped deep green leaves (to 8” long). Each stem is topped with 1 or 2 but sometimes an umbel of up to 10 flowers. Flowers are followed by seedpods that remain attractive in the garden or for dried arrangements. Each plant may produce from 6 to 30 flowers.
Genus name comes from the Latin name meaning lily.
Specific epithet means of the island of Formosa (Taiwan).
Problems
For the average gardener, this lily is easy to grow. It is generally pest free, but potential diseases include: (1) lily mosaic virus (prompt control of aphids which vector the disease is highly recommended, since there is no cure once infection occurs), (2) bulb rot (particularly in wet, poorly-drained soils), and (3) Botrytis. Taller plants may need staking if grown in too much shade (stems weaken) or in locations exposed to strong winds. May be short-lived.
Uses
Showy flowers for borders, cottage gardens or cutting gardens. Also may be grown in pots or containers, but plants and flowers will be somewhat smaller.