Also known as slipper orchids, moccasin flower, camel’s foot, squirrel foot, steeple cap, Venus’ shoes, and whippoorwill shoe, lady slipper orchids are a member of the orchid family, Orchidaceae, that is one of the two largest plant families and includes the vanilla plant. Most lady’s slipper orchids grow in temperate and subtropical climates of the Northern Hemisphere and are found in such habitats as moist woods, wetlands, and rocky outcrops. Plants are perennial, mostly terrestrial, and grow from a short hefty rhizome. Most slipper orchids have one or more erect stems 6-30″ tall, carrying 2-12 hairy leaves that are ovate to elliptic, to lanceolate, 1.5-10″ long, and pleated longitudinally. One to three (but up to 12) flowers appear at the tops of the leafy stems. The flowers have a showy inflated pouch (the slipper) that is yellow, white or pink and may be tinged or marked with other colors, inside and/or out. Sepals and petals are often the same color ranging from white to green to brown,, and may be spirally twisted. Bees are the most common pollinators but other insects may also be involved.
Most lady’s slippers prefer cool temperatures, part shade and moist soil, and are dependent on special soil fungi to complete their life cycle. Slugs are an occasional problem and shoot rot can occur if plants are watered excessively during their dormant period. Lady slippers are difficult to propagate and to grow in the garden and most harvested from the wild will die when transplanted. A few nurseries specialize in growing lady’s slippers and a limited number of species are available.
The genus name, Cypripedium, is derived from ancient Greek words Κύπρις (Kúpris), referring to the Greek goddess Aphrodite, and πέδιλον (pédilon), meaning sandal.
Photo Credit: Wikipedia
The environmental conditions of the Rocky Mountain area have resulted in at least four species of lady’s slipper native to the Rocky Mountain area but may be native to other areas in the US also. The lady’s slippers described here are native to at least one of the states in the Rocky Mountain area.
Clustered Lady’s Slipper (Cypripedium fasciculatum)
Short hairy stems bear two opposite rounded leaves that are 1.5-4″ long, pleated and often lie near the ground. Flowering stems bear a cluster of 2-9 terminal nodding flowers that may rest on the leaves or the ground. The flowers have a yellowish-green pouch with purple streaking near the opening, and green to purplish-brown sepals and petals. Photo Credit: Andrey Zharkikh, Wikimedia Commons
Alternate Name/s: Brownie lady’s slipper
Native Range: Washington, Oregon and California as well as parts of the Rocky Mountain area
Habitat: At high elevations in open coniferous forests, shrublands or thickets, and along stream banks on fairly steep slopes
Type: Perennial
Height: 12″
Bloom Time: Spring to summer
Bloom Color: Yellowish green, greenish brown to purplish brown to nearly red
Light: Partial to full shade
Soil: Moist to dry, well drained
USDA Hardiness Zones: Unavailable
Photo Credit: Wikipedia
Large Lady’s Slipper (Cypripedium montanum)
Stems carry 4-6, usually 5, plicated leaves that are broadly elliptic and 2-6″ long. One to three sweet-scented flower appear singly in each of the upper leaf axils. The pouch is .8 to 1.2″ long, and white with faintly purple veining near the base and purple spots inside. The sepals and petals are brownish purple, narrow and usually wavy and twisted.
Alternate Name/s: Mountain lady’s slipper, white lady’s slipper, moccasin flower
Native Range: Idaho, Montana and Wyoming as well as areas on the Pacific Coast
Habitat: Open mixed conifer or mixed conifer hardwood forests, forest openings, shrub thickets and alpine meadows in dry to moist soil, at elevations 1600 to 6900 feet.
Type: Perennial
Height: 8-28″
Bloom Time: Late spring to mid-summer
Bloom Color: White
Light: Part shade to sun
Soil: Dry to moist, well-drained; tolerates drier soil than most lady’s slippers
USDA Hardiness Zones: Unavailable
Photo Credit: US Forest Service, Wikimedia Commons
Greater Yellow Lady’s Slipper (Cypripedium parviflorum)
Hairy stems carry 2-5 clasping leaves that are 1.5- 6.5″ long, elliptical to oval, and hairy, and have distinct parallel veining. One to two terminal flowers have a pale to dark yellow pouch (rarely white) that is .75-1.25″ long and may have reddish to purplish spots on the pouch opening and faint purple venation on its lower area. Green, yellowish, or dark purple/brown sepals and petals are 2″ long and usually spirally twisted. Yellow lady’s slipper is one of the easier ones to grow so is a good choice for native plant, woodland, shade, meadow, prairie, and pollinator gardens.
Alternate Name/s: Yellow lady’s slipper, lesser yellow lady’s slipper, moccasin flower
Native Range: Washington, Oregon, and California as well as places on the, Rocky Mountain area, Southwest, Midwest, Southeast, Mid-Atlantic and New England
Habitat: Dry to mesic forests, woodlands, fens, prairies, meadows and along streams.
Type: Perennial
Height: 6-17″
Bloom Time: Late spring to early summer
Bloom Color: Yellow
Light: Part shade
Soil: Compost, medium moist, well-drained, acidic
USDA Hardiness Zones: 3-8
Photo Credit: Wikipedia
Sparrow’s egg lady’s slipper (Cypripedium passerinum)
Each of several stems of the plant carries 3 to 7 oval to lance-shaped, clasping leaves that are up to 7.5″ long, hairy, and sticky. One or two terminal flowers per stem have a white, rarely pink-tinged, egg-shaped pouch that is .5-4.7″ long and has purplish spotting at the base, the opening and inside. Two flat white petals are on either side of the pouch and a green sepal partially covers the petals including the pouch.
Alternate Name/s: Small white Northern lady’s slipper, Franklyn’s lady’s slipper
Native Range: Montana as well as in parts of Canada and Alaska
Habitat: Moist spruce forests at low elevations, tundra, mixed woodlands thickets, dunes, sphagnum bogs, river terraces, lakeshores, and streambanks
Type: Perennial
Height: 20″
Bloom Time: Summer
Bloom Color: White
Light: Part shade
Soil: Low organic matter, moist to dry, well-drained
USDA Hardiness Zones: Unavailable but probably grows in zones 2-6 ; does not like warm summers.
Photo Credit: Wikipedia
Six states are included in the Rocky Mountains area: Montana, Wyoming, Idaho, Colorado, Utah, and Nevada. The geography is diverse and includes mountains, plains, and deserts, and the climatic conditions are variable and vary with the geography. Low annual rainfall and high temperatures are typical of some parts of the area, while snowfall and low temperatures are found in other parts and the mountains of all of these states.