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Cypripedium reginae
Also called Queen Lady's Slipper, Large White Lady's Slipper, Showy Lady Slippers, Showy Ladyslipper
A rare, large terrestrial orchid of northern North American wetlands with showy white and rose-pink flowers. It grows best in cool, moist, loose soil in partial shade, and is very hard to raise from seed.
Cypripedium reginae, known as the showy lady's slipper, pink lady's-slipper, or the queen's lady's-slipper, is a rare lady's-slipper orchid native to northern North America. Although never common, this plant has vanished from much of its historical range due to habitat loss. It is the state flower of Minnesota.
The showy lady's slipper has been a subject of horticultural interest for many years, and was known to Charles Darwin who, like many, was unsuccessful in cultivating the plant.
It has low seed germination rates and slow maturation to flowering. This makes it more vulnerable to illegal collection. It was historically difficult to raise from seed in sterile culture or in greenhouse conditions, taking many months to germinate in sterile culture. In the 1990s a group of high school students in New Hampshire, under the direction of Dr. Peter Faletra, made substantial progress on axenic culture from seed and were able to obtain over 50% germination levels in about 3 weeks. Efforts at micropropagation have had marginal success.
Cypripedium reginae contains an irritant, cypripedin, a phenanthrenequinone. The plant is known to cause dermatitis on the hands and face. The first report of the allergy reaction was in 1875 by H. H. Babcock in the United States, 35 years before the term "allergy" was coined. The allergen was later isolated in West Germany by Bjorn M. Hausen and associates.
Cypripedium reginae grows in wetlands such as fens, wooded swamps, and riverbanks. Cyp. reginae thrives in neutral to basic soils but can be found in slightly acidic conditions. The plants often form in clumps by branching of the underground rhizomes. Its roots are typically within a few inches of the top of the soil. It prefers very loose soils and when growing in fens it will most often be found in mossy hummocks.
Text excerpted from the Wikipedia article Cypripedium reginae by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.
The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.
Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.
