Culture
Winter hardy to USDA Zones 7-9. Best grown in deep, fertile, humusy, organically rich, moist but well-drained soils in part shade. Best sited in locations sheltered from strong winds. Fertilization helps develop bulb offsets. Mulch in winter. Plant new bulbs with the tips at the soil surface in early spring. Propagation is by bulb offsets and seed. Dig up and remove offsets after plants flower. Offsets may take 4-5 years to flower. Sow seed in bulb trays. Plant new seedlings each year to increase the number of plants which in turn helps insure some flower production each year.
Noteworthy Characteristics
Cardiocrinum giganteum, commonly called giant lily, is a bulbous perennial that is native to part shade woodland areas of the Himalayas, China and Myanmar. Nodding, fragrant, trumpet-shaped, lily-like, white flowers (to 8" long) with a greenish tinge on the outer petals, each with purple adaxial streaking, bloom in terminal racemes in summer atop thick, straight, rigid, stems growing up to 9' tall. Stems rise up from a basal rosette of glossy, broad-ovate, cordate-based, hosta-like, medium to dark green leaves (each to 12-15" long). Stem leaves are smaller. Each raceme has up to 20 flowers. Bulb dies after flowers bloom, but bulb offsets remain. Flowers are followed by decorative seed capsules (to 2 1/2" long).
Var. yunnanense differs from the species by shorter height (6-7' tall), smaller flowers (to 6" long) with narrower petals, and the outer part of the flower is white and the inside is streaked with purplish red. The young leaves are tinged with bronze-red. Native range includes Yunnan province in China.
Genus name comes from the Greek words kardia meaning a heart and krinon meaning lily in reference to the heart-shaped leaves.
Specific epithet means unusually large or tall.
Problems
Requires considerable effort to grow this plant well. Watch for snails and slugs. Some susceptibility to lily mosaic virus (prompt control of aphids which vector the disease is highly recommended since there is no cure once infection occurs). Bulb rot (particularly in wet, poorly drained soils) may occur. Botrytis will require fungicide applications.
Uses
Woodland gardens. Part shade areas of border. Sundappled areas shaded by large trees.