Host an Event Volunteer Join Tickets

Support the plant database you love!


Plant Database

Search for native plants by scientific name, common name or family. If you are not sure what you are looking for, try the Combination Search or our Recommended Species lists.

Enter a Plant Name:
Or you can choose a plant family:
Cypripedium acaule (Moccasin flower)
Cressler, Alan

Cypripedium acaule

Cypripedium acaule Aiton

Moccasin Flower, Pink Lady's Slipper

Orchidaceae (Orchid Family)

Synonym(s): Fissipes acaulis

USDA Symbol: CYAC3

USDA Native Status: L48 (N), CAN (N), SPM (N)

A leafless stalk bears 1 flower (rarely 2) with a distinctive pink, inflated, slipper-like lip petal, veined with red and with a fissure down the front.

This is one of the largest native Orchids and is found both in low, sandy woods and in higher, rocky woods of mountains. At times several hundred of these striking flowers can be counted within a small area. Nevertheless, like other woodland wildflowers it should not be picked. These Orchids propagate poorly and are very difficult to grow in wildflower gardens. The genus name derives from the Latin for "Venus' slipper."


From the Image Gallery

56 photo(s) available in the Image Gallery

Plant Characteristics

Duration: Perennial
Habit: Herb
Leaf Complexity: Simple
Fruit Type: Capsule
Size Notes: Up to about 2 feet tall.

Bloom Information

Bloom Color: Pink , Green , Purple , Brown
Bloom Time: Apr , May , Jun , Jul


USA: AL , CT , DC , DE , GA , IL , IN , KY , MA , MD , ME , MI , MN , NC , NH , NJ , NY , OH , PA , RI , SC , TN , VA , VT , WI , WV
Canada: NB , NL , NS , ON , PE , SK
Native Distribution: Saskatchewan to Newfoundland and Nova Scotia; south to South Carolina and Georgia; west to Alabama and Tennessee; north to Minnesota.
Native Habitat: Dry forests, especially pine woods; often in humus mats covering rock outcrops; occasionally in moist woods.

Growing Conditions

Light Requirement: Part Shade , Shade
Soil Moisture: Dry , Moist
Soil Description: Sandy


Use Medicinal: Sedative and nerve medicine, cure for insomnia, teaspoon of powdered root in sugar-water. (Weiner)
Warning: The plants of the genus Cypripedium have glandular hairs on the leaves and stems that can cause a rash, similar to poison ivy rash, upon contact. POISONOUS PARTS: Glandular, irritating hairs on leaves. Symptoms include skin irritation after contact. Toxic Principle: Unidentified.
Conspicuous Flowers: yes

National Wetland Indicator Status

This information is derived from the U.S. Army Corps of Engineers National Wetland Plant List, Version 3.1 (Lichvar, R.W. 2013. The National Wetland Plant List: 2013 wetland ratings. Phytoneuron 2013-49: 1-241). Click here for map of regions.

From the National Organizations Directory

According to the species list provided by Affiliate Organizations, this plant is on display at the following locations:

Mt. Cuba Center - Hockessin, DE


Bibref 1207 - Earth Medicine, Earth Food (1990) Michael A. Weiner

Search More Titles in Bibliography

Web Reference

Webref 38 - Flora of North America (2019) Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
Webref 23 - Southwest Environmental Information Network (2009) SEINet - Arizona Chapter

From the Archive

Wildflower Newsletter 1990 VOL. 7, NO.4 - Research Update, Wild-Collecting Endangers Natives, Director's Report, Maryland ...
Wildflower Newsletter 1992 VOL. 9, NO.6 - Architectural Plans for new Facility Taking Shape, Native Plants Provide Local C...

Additional resources

USDA: Find Cypripedium acaule in USDA Plants
FNA: Find Cypripedium acaule in the Flora of North America (if available)
Google: Search Google for Cypripedium acaule


Record Modified: 2023-04-24
Research By: TWC Staff

Go back