Cardiocrinum giganteum aka Giant Himalayan Lily

Cardiocrinum giganteum is a challenging plant that requires patience and specific growing conditions. It takes 5-7 years to flower from seed, and the mother bulb dies after flowering (monocarpic), though it produces offset bulblets that will flower in 3-5 years. The plant is intolerant of hot, sunny conditions and requires consistent moisture without waterlogging. Protection from slugs, snails, and lily beetles is essential, as is ensuring proper drainage to prevent bulb rot.

Cardiocrinum giganteum requires consistently moist but well-drained soil. Water regularly during the growing season to maintain moisture, particularly during dry spells, but avoid waterlogging which can cause bulb rot. The soil should never dry out completely, especially in summer. In their native Himalayan woodland habitat, these plants receive regular rainfall and grow in moisture-retentive humus-rich soil.

Cardiocrinum giganteum thrives in deep, humus-rich, fertile soil similar to natural woodland conditions. The soil should be moisture-retentive yet well-drained to prevent bulb rot. The plant tolerates a range of pH from mildly acidic to alkaline. Avoid thin, dry, or poorly-drained soils.

Cardiocrinum giganteum requires partial shade or dappled woodland light. It is intolerant of hot, sunny positions where the large heart-shaped leaves are prone to burning. Ideal locations include beneath deciduous trees that provide filtered light, or on the north side of buildings or hedges. Plant among larger shrubs or trees that provide wind protection. The plant naturally grows in woodland clearings and forest edges in its Himalayan habitat.

Cardiocrinum giganteum prefers the cool, moist conditions typical of its native Himalayan woodland habitat. While it doesn't require tropical humidity, it benefits from the naturally humid microclimate found beneath trees and in sheltered garden positions. In drier climates, mulching around the base helps maintain moisture. The plant is best suited to temperate climates with regular rainfall and cool summers.

Cardiocrinum giganteum is a hungry feeder that benefits from rich, fertile soil and regular feeding. Apply a thick mulch of well-rotted leaf mould or compost annually in spring. A balanced organic fertilizer or slow-release feed can be applied in early spring as growth begins. The plant naturally grows in humus-rich woodland soil, so maintaining high organic matter content is key to strong growth and eventual flowering.

Cardiocrinum giganteum can be propagated from seed or by offset division. Seeds require cold stratification and hypogeal germination—they grow underground the first year and don't produce leaves until the following spring. Expect 5-7 years from seed to flowering. The easier method is dividing offset bulblets that form around the base of flowering plants; these typically bloom in 3-5 years.

Cardiocrinum giganteum is the largest species in the lily family, with flower stalks reaching 2-4 metres tall depending on growing conditions. The basal rosette of heart-shaped leaves spreads about 30-60cm. Growth is very slow, with plants taking 5-7 years from seed to reach flowering size. The variety yunnanense is smaller, reaching 1-2 metres. Once flowering size is reached, the plant is monocarpic—it flowers, sets seed, and dies, leaving offset bulblets to continue the display.

Cardiocrinum giganteum flowers in summer, typically June to August. Each tall stem produces a raceme of 15-20 or more large, nodding, trumpet-shaped flowers that can measure over 15cm long. The blooms are creamy white with distinctive reddish-purple streaking inside. The flowers emit a powerful sweet, spicy fragrance, particularly intense in the evening. Being monocarpic, each bulb flowers only once before dying, but produces offset bulblets that will flower in subsequent years.

Cardiocrinum giganteum produces one of the most intoxicating fragrances in the plant world. The large white trumpet flowers emit a rich, sweet, oriental perfume that is particularly powerful in the evening. Pacific Bulb Society describes it as 'a heavy oriental, sweet but spicy scent'. This evening-intensified fragrance is typical of flowers that attract moth pollinators. The scent alone makes this challenging plant worth growing for many gardeners.

Two recognized varieties of Cardiocrinum giganteum exist. The typical variety giganteum grows up to 3 metres tall with greenish-white flowers streaked purple inside—this is the most commonly cultivated form. Variety yunnanense from Yunnan Province, China, is smaller at 1-2 metres with pure white flowers marked purple-red inside. Both share the same cultural requirements, though var. yunnanense may be slightly easier to accommodate in smaller gardens.

Cardiocrinum giganteum is exclusively an outdoor plant best suited to USDA zones 6-9 (UK hardiness zone 7). It requires temperate woodland conditions and cannot be grown as a houseplant due to its size (2-4m tall) and cultural needs. The plant is frost hardy but vulnerable to winter wet—ensure excellent drainage to prevent bulb rot. Spring frosts can damage emerging foliage, so a sheltered position is beneficial. In regions with hot summers, extra shade and moisture are essential.

In spring, protect emerging shoots from late frosts with fleece if necessary and begin regular watering as growth starts. Apply mulch and fertilizer in early spring. Through summer, maintain consistent moisture and watch for pests. Tall flower stalks may need staking for support. In autumn, plant new bulbs shallowly with tips just visible. Winter protection from excessive wet is more important than cold protection.

Cardiocrinum giganteum is susceptible to several pests and diseases. Slugs and snails are major problems, especially for young growth and bulbs. Lily beetle (small scarlet-red beetles) can devastate foliage and flowers. Mice and voles may eat dormant bulbs. Aphids can transmit lily mosaic virus, for which there is no cure—control aphids promptly. Bulb rot occurs in waterlogged soil, and Botrytis (grey mould) may require fungicide treatment. Good drainage and vigilant pest control are essential.

Cardiocrinum giganteum is a temperate climate plant hardy to USDA zones 6-9. It tolerates winter cold well but is vulnerable to late spring frosts which can damage emerging foliage. NC State notes plants can be 'injured below 28°F (-2°C)'. The plant prefers cool summer temperatures and struggles in hot climates—in its native Himalayan habitat it grows at 1,500-3,600m elevation where summers are cool. Provide shade and extra moisture where summers are warm.

Cardiocrinum giganteum has limited traditional medicinal uses, rated 1 out of 5 by PFAF. In traditional practice, the leaves have been applied externally as a poultice for wounds and bruises. The root has been used as a paste applied to dislocated bones. These are folk remedies and the plant is not used in modern medicine. As with all plants, caution should be exercised and professional medical advice sought rather than self-treating with plant preparations.

Cardiocrinum giganteum has minimal practical uses beyond its ornamental value, rated 1 out of 5 by PFAF. The hollow flower stems have traditionally been used for making flutes. The plant is primarily grown as a dramatic ornamental for woodland gardens, valued for its towering stature, spectacular flowers, and exceptional fragrance.

Giant Himalayan Lily’s native range is E. Asia - Himalayas from Nepal to Assam and Sikkim.

Ploi's records do not contain confirmed information on the toxicity of this particular plant. In the event of accidental ingestion of plant material with questionable toxicity by you, a family member, or a pet, it is always a good idea to consult a healthcare professional.