Common Name: Fairyslipper

General Information

Calypso bulbosa is a herbaceous perennial plant producing a solitary, basal leaf 3 - 6cm long from an underground corm. It produces an erect flowering stem 5 - 20cm tall, usually with only one flower, occasionally two[]
The plant was traditionally harvested from the wild for local use as a food and a medicine.
Although Calypso bulbosa has a very wide range, it is highly susceptible to even slight disturbances in its environment. Trampling and picking are the primary reasons for its rapid decline in some locations. Picking the flower inevitably kills the plant, because the delicate roots break at even the lightest pull on the stem. A decline in the frequency of the plant, due largely to a growing illegal international trade, caused the International Union for the Conservation of Nature and Natural Resources to list it as a species vulnerable to extinction on a global scale. Transplanting or cultivating the plant is rarely successful because of its need for specific soil fungi that are not usually present on transplant sites or in controlled environments[].

Known Hazards

None known

Botanical References

, ,

Range

Circumboreal through northern Europe and Asia. In N. America it extends southwards on the west coast to California and on the east to New York.

Habitat

Soils rich with decaying leaves and wood, in moist pine or spruce woods and by cool shady streams from sea level to the mid-montane zone[, ].

Properties

Edibility Rating
Medicinal Rating
Habit	Corm
Height	0.10 m
Pollinators	Insects
Self-fertile	No
Cultivation Status	Wild

Cultivation Details

Grows well in half shade in a light moist organic-rich soil[, , ]. Requires a lime-free soil, doing best in full shade[].
The plant comes into growth in the autumn and, although fairly hardy, is best grown in a frame or unheated greenhouse[].
Following flowering, the current year's corm gives rise to one shoot bud that forms a pair of root primordia. The root buds elongate as the shoot elongates and expands to form the new corm. The parent corm persists, and its leaf withers. By the end of the growing season, the new shoot has formed, and a leaf arises from its apex and overwinters[].
Orchids are, in general, shallow-rooting plants of well-drained low-fertility soils. Their symbiotic relationship with a fungus in the soil allows them to obtain sufficient nutrients and be able to compete successfully with other plants. They are very sensitive to the addition of fertilizers or fungicides since these can harm the symbiotic fungus and thus kill the orchid[].
Plants can be naturalized in the woodland or bog garden[]. Apply a good organic mulch in the winter[].
Plants do not always grow every year, the bulb can remain dormant in the soil for 2 years[].

Edible Uses

Corm - raw or cooked[, , , , ]. Rather small[]. The corms have a rich, butter-like quality[]. They were usually boiled by the North American Indians before being eaten, though young maidens would eat them raw as they were believed to increase the size of the bust[].

Medicinal

The corms have been chewed or the flowers sucked in the treatment of mild epilepsy[].

Other Uses

None known

Propagation

Seed - we have no information on this species but, like all members of the orchid family, the seed of this species is extremely simple, it has a minute embryo surrounded by a single layer of protective cells. It contains very little food reserves and depends upon a symbiotic relationship with a species of soil-dwelling fungus. The fungal hyphae invade the seed and enter the cells of the embryo. The orchid soon begins to digest the fungal tissue and this acts as a food supply for the plant until it is able to obtain nutrients from decaying material in the soil[]. Surface sow the seed, preferably as soon as it is ripe, in the greenhouse and do not allow the compost to dry out. It is best to use some of the soil that is growing around established plants in order to introduce the fungus, or to sow the seed around a plant of the same species and allow the seedlings to grow on until they are large enough to move.
Division in autumn. Make sure that you keep plenty of soil with each plant. It is also said to be possible to transplant orchids after they have flowered but whilst they are still in leaf. Grow on for at least the first year before potting up and do not plant out until the plants are 2 - 4 years old.
Division of the tubers as the flowers fade[]. This species produces a new tuber towards the end of its growing season. If this is removed from the plant as its flowers are fading, the shock to the plant can stimulate new tubers to be formed. The tuber should be treated as being dormant, whilst the remaining plant should be encouraged to continue in growth in order to give it time to produce new tubers[].
Division can also be carried out when the plant has a fully developed rosette of leaves but before it comes into flower[]. The entire new growth is removed from the old tuber from which it has arisen and is potted up, the cut being made towards the bottom of the stem but leaving one or two roots still attached to the old tuber. This can often be done without digging up the plant. The old tuber should develop one or two new growths, whilst the new rosette should continue in growth and flower normally[].