Cardiocrinum giganteum, 'Giant Yunnan Lily'

Cardiocrinum giganteum, 'Giant Yunnan Lily' is a truly spectacular plant, which produces glorious vanilla scented, trumpet-like flowers on stems up two to three metres tall.
It originates from forest floors in China so will thrive in moist, semi-shaded positions. The plants produce two inch thick stems, with dinner plate sized leaves.
The stately flower-spikes bear glowing, 15 to 20cm (6 to 8in) long lily-like, creamy-white blooms that have a claret stripe in the throat. Flowering in June to August, they are held above the green foliage which often has a bronze/purple tinge. A showstopper.

Cardiocrinum giganteum is a fantastic plant in all respects, but they are a long term project, not an instant gratification plant. They need little effort and maintenance other than pricking out from germinating and potting on, but if you want the best from them, they need to be given patience and time.
Most gardeners agree growing this rare beauty is well worth the wait. I suppose you do have to be patient to be a gardener. We all know the longer we must wait for a beauty, the more we treasure it.

The plants are fully hardy and adore light shade, humidity and rich, leafy soils. Prepare your soil well in advance with plenty of humus, leaf mould, manure and bark to get the best from them.
The plant is monocarpic, and after flowering they die leaving offsets which flower quicker in 3 to 5 years. The flowers produce enormous toothed seed-pods when dried. Planting in successive years or in different sizes ensures a cycle of flowering.

Sowing: Sow indoors at any time of year.
Sow as soon as possible. Keep the seeds in the fridge until you are ready to sow.
Sow seeds in a pot of peaty compost at a depth of around 1/16in (2mm) and cover them with fine gravel or grit. The gravel holds the seeds in place and keeps the moisture at the soil surface.
Put in a cool dark place protected from mice. Artificial heat is not needed and in some cases will prevent the seeds from germinating.
Germination can be very slow, the seeds often need two periods of cold moist conditions with a warm growing period in between. The seeds should germinate in spring but may germinate in their second year, so patience is needed. Keep the compost moist at all times and, if needed clean the tray, replacing the grit in the second year.

Transplanting:
Allow the seedlings to grow in a shaded cold frame and protect them over the following winter. The new plants can be put into the garden the following spring. Transplant the seedlings when large enough to handle into 7.5cm (3in) pots. Plant out the following spring into a nursery bed and grow on for 3 to 4 years before planting into final site in spring.
Plant the roots just below the soil surface. Top-dress annually with leaf mould and provide a deep winter mulch. Plant 90cm (3ft) apart. The plants prefers to be planted in light shade.

Cultivation:
Many references will tell you that the cardiocrinum's bulbs have a hapaxanthic or monocarpic life history (meaning they die after they flower).
While this is a true statement, it is slightly misleading. Yes, the flowering stems die after they flower but the bulb, which took several years to store up the large supply of food needed to produce this gigantic flower stem, multiplies itself by producing small offset bulbs around the base of the stem. Though flowering uses up all the food in the main bulb, the offsets (which are clones of the main bulb) continue to grow and flower in future years. In the autumn when you remove the dead stock and the seedpod, separate the bulblets and replant them in a permanent location (70 to 90cm or 2.3 to 3ft apart). The bulbs need to be separated and spread out to prevent overcrowding to ensure that each achieves its maximum growth potential. They will bloom in three to five years (not as much patience needed this time). From one bulb you can eventually get a sizeable stand of plants.

Position:
Large groupings create a stand where bulbs of all ages are mixed and provide a few blooming plants each year. Given a suitable location, a stand of these lilies will establish itself and produce a regular cycle of flowers. Woodland settings are ideal. These lilies need a shady location where direct sun will not sunburn their leaves. Filtered shade works if the roots are protected with mulch. Hot summer temperatures may cause die-out. Bulbs are hardy with winter mulch.
Having larger trees and shrubs also protects them from strong winds that might break their stems or knock them over. Wherever you site them, be sure they are sheltered from the wind as you would not want to have to stake them.
Soil should be loose and moisture-retentive but well-drained and rich in nutrients. Standing water rots the bulbs. As they are heavy feeders, give them lots of compost and leaf mould. You may supplement this with slow release organic fertilizer in spring. Where possible, site them where they can be viewed from a distance as a group rising from a low border. Since their leaves are not attractive in late summer and fall (slug damage), keep them away from the front of the beds. Woodland groundcovers help hide decaying foliage.
Combine your cardiocrinum with companions that like similar conditions. Rhododendrons, camellias, azaleas and hydrangeas are good backgrounds. Also, true lilies, astilbes, primulas and low-growing hardy fuchsias all work well. Once the bulbs have become established and begin to enlarge, cardiocrinums resent being moved. If moved, they tend to become stunted, so pick the right spot the first time.

Plant Uses:
Exotic garden, specimen plant, woodland garden

Origin:
Cardiocrinum giganteum is found in the Himalayas of India, Tibet, Nepal, Bhutan, Pakistan, China and Myanmar (Burma). It was first described by Nathaniel Wallich in Nepal and was introduced into commercial production (as Lilium giganteum) in Britain in the 1850s.
A bulb grown from seed collected by Major Madden flowered in Edinburgh in July 1852, while those collected by Thomas Lobb were first exhibited in flower in May 1853.
Cardiocrinum is a small genus in the lily family (Liliaceae). Though closely related to true lilies (lilium), one distinguishing feature separating the genus cardiocrinum from the genus of true lilies is its notable wide heart-shaped leaves with branched veins (true lilies have strap-shaped leaves).
Three species of this Asian native are grown in cultivation and can be found for sale - Cardiocrinum cordatum, C. giganteum and C. cathayanum. But the most widely known, C. giganteum, is the spectacular giant Himalayan lily.

Nomenclature:
The large leaves of Cardiocrinum give rise to its genus name. It derives from the Greek words kardio for heart and krinum for lily - meaning 'heart lily'.
They weren't kidding when they called this plant 'giganteum' meaning 'a giant'. The giant stem can have as many as 20 to 40 flower buds on it.