Flower profile

Pink lady's slipper

Cypripedium acaule

Pink lady's slipper (Cypripedium acaule) is a flowering plant in the Orchidaceae family, native in the lower 48 states, blooming mostly April–June across the U.S.

★ Official state wildflower of New Hampshire (1991)Native in the lower 48

A woodland orchid with a puffy pink pouch, and New Hampshire's official state wildflower. It's also called the moccasin flower.

25states where USDA records it

18Bloomipedia state lists include it

50,965U.S. sightings*

*iNaturalist research-grade observations, as of October 17, 2026.

On our lists for: Connecticut, Delaware, Kentucky, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, North Carolina, Pennsylvania, Rhode Island, Tennessee, Vermont, Virginia, West Virginia, Wisconsin

🏅

New Hampshire's official state wildflower since 1991. Visit the New Hampshire page → ^{N.H. RSA 3:17}

Fun facts

New Hampshire named it the official state wildflower in 1991. It's also the provincial flower of Prince Edward Island, Canada. ^{N.H. RSA ch. 3 Wikipedia}
It's an orchid (family Orchidaceae), native to eastern North America. ^{Wikipedia USDA PLANTS}
Its scientific name, acaule, means "lacking an obvious stem," which is why it's also called the stemless lady's-slipper. ^Wikipedia
Each plant makes just one flower per season, on a stalk rising between two large leaves at the base. ^Wikipedia
Unlike most lady's slippers, its pouch opens through a slit down the front instead of a round hole. ^Wikipedia
It's a bit of a trickster: it offers bees no nectar at all. Its main pollinators are thought to be bumblebee queens. ^Wikipedia
It thrives in very acidic soil (often pH 4–4.5) and relies on fungal partners in its roots. ^Wikipedia
It takes many years to grow from seed to a mature plant, so it's best admired right where it grows. ^Wikipedia

✨ Did you know?

Minnesota's state flower is a lady's slipper too, but a different species: the pink and white lady's slipper (Cypripedium reginae). ^{Wikipedia: List of U.S. state flowers}

When does it bloom?

Flowering records by month across the U.S. (iNaturalist research-grade observations marked “Flowering”) (18,494 records)

Bloom time in the 18 states whose Bloomipedia list includes it

State	Type	Peak bloom	Sightings*
Massachusetts	Native	May–June	8,764
New Hampshire	Native	May–June	5,286
New York	Native	May–June	4,090
Maine	Native	May–June	3,917
Michigan	Native	May–June	3,414
Virginia	Native	April–May	3,400
North Carolina	Native	April–May	3,076
Pennsylvania	Native	May	2,291
Vermont	Native	May–June	2,113
Maryland	Native	April–May	1,851
Tennessee	Native	April–May	1,839
New Jersey	Native	May	1,786
Wisconsin	Native	May–June	1,755
Connecticut	Native	May–June	1,575
West Virginia	Native	May–June	875
Kentucky	Native	April–May	813
Rhode Island	Native	May–June	617
Delaware	Native	April–May	296

Conservation status

Federal (U.S. ESA)

Not listed No U.S. Endangered Species Act listing in the USFWS ECOS database. ^{USFWS ECOS}

NatureServe global

G5 Secure worldwide. ^NatureServe

State rare plant lists

Not listed Not on the official rare plant list in 16 of our 18 states.

See each state

Massachusetts: Not listed Not on Massachusetts Endangered Species Act list (321 CMR 10.90). NatureServe: SNR, not yet ranked in Massachusetts. ^{MESA list}
New Hampshire: Not listed Not on New Hampshire Official Rare Plants List (Ncr 312, eff. Jan 1, 2020). NatureServe: SNR, not yet ranked in New Hampshire. ^{NH Ncr 312}
Maine: Not listed Not on Maine Rare Plant List (Maine Natural Areas Program, 2021). E and T are Maine's official endangered and threatened plants (12 M.R.S.); SC and PE are tracking categories. NatureServe: SNR, not yet ranked in Maine. ^{Maine rare plant list}
Michigan: Not listed Not on Michigan endangered and threatened plants (Mich. Admin. Code R 299.1028, eff. March 20, 2023). NatureServe: SNR, not yet ranked in Michigan. ^{R 299.1028}
Virginia: Not listed Not on Virginia endangered and threatened plant and insect species (2VAC5-320-10). NatureServe: S5, secure in Virginia. ^2VAC5-320-10
North Carolina: Not listed Not on North Carolina Protected Plant Species List (02 NCAC 48F .0301). NatureServe: S5, secure in North Carolina. ^{02 NCAC 48F .0301}
Pennsylvania: Not listed Not on Pennsylvania classified native plants (17 Pa. Code Ch. 45, Subchapter B, as amended 2023). NatureServe: S5, secure in Pennsylvania. ^{17 Pa. Code Ch. 45}
Vermont: Not listed Not on Endangered and Threatened Plants of Vermont (10 V.S.A. chap. 123; list of Feb 10, 2022). NatureServe: S5, secure in Vermont. ^{Vermont E&T list}
Maryland: Not listed Not on Maryland threatened and endangered plants (COMAR 08.03.08.05, .06 and .08). NatureServe: SNR, not yet ranked in Maryland. ^{COMAR 08.03.08}
Tennessee: Not listed Not on Tennessee endangered plants (Tenn. Comp. R. & Regs. 0400-06-02-.04, Rare Plant Protection and Conservation Act). NatureServe: S4, apparently secure in Tennessee. ^{TN rule 0400-06-02-.04}
New Jersey: Not listed Not on New Jersey Endangered Plant Species List (N.J.A.C. 7:5C-5.1). NatureServe: S4, apparently secure in New Jersey. ^{N.J.A.C. 7:5C-5.1}
Wisconsin: Not listed Not on Wisconsin endangered and threatened species list (Wis. Admin. Code NR 27.03). NatureServe: SNR, not yet ranked in Wisconsin. ^{NR 27.03}
Connecticut: Not listed Not on Connecticut Endangered, Threatened and Special Concern Plants (RCSA 26-306; 2015 list). NatureServe: SNR, not yet ranked in Connecticut. ^{CT E/T/SC list}
Kentucky: Not listed Not on Kentucky endangered and threatened plant lists (400 KAR 3:040, eff. 2026). NatureServe: S4, apparently secure in Kentucky. ^{400 KAR 3:040}
Rhode Island: Not listed Not on Rhode Island Rare Plants 2016 (RI Natural History Survey, from the RI Wildlife Action Plan; informational, Rhode Island has no state plant-protection listing law). NatureServe: S4, apparently secure in Rhode Island. ^{RI rare plants 2016}
Delaware: Not listed Not on Rare and Uncommon Plants of Delaware (DNREC, 2024; informational, Delaware has no state plant-protection list). NatureServe: S4, apparently secure in Delaware. ^{DE rare plants 2024}

New York

Exploitably vulnerable On New York protected native plants (6 NYCRR § 193.3): exploitably vulnerable (protected from picking without the landowner's permission). NatureServe: S4, apparently secure in New York. ^{6 NYCRR § 193.3}

West Virginia

No list West Virginia has no state law listing endangered or threatened plants (only federally listed species are protected), so we show NatureServe's West Virginia ranks instead. NatureServe: S5, secure in West Virginia.

Rare elsewhere

Other states where NatureServe ranks it rare or missing: IL (SH), IN (S1). (S1 critically imperiled, S2 imperiled, SH possibly extirpated, SX presumed extirpated.)

Checked October 17, 2026. Rankings and lists can change, so follow the links for the latest.

Please leave it where it grows

Please don't pick or dig lady's slippers. They take many years to grow from seed to flower and rely on fungal partners in the soil. Wikipedia reports the species is listed as endangered in Illinois and Tennessee. In New Hampshire, two of its relatives, the showy lady's-slipper and the ram's-head lady's-slipper, are state-endangered. Also: it's on New York's rare plant list (exploitably vulnerable). ^{Wikipedia NH Ncr 312 6 NYCRR § 193.3}

Can you eat it?

For peopleNot edible: can irritate skin

NC State Extension lists it as poisonous to humans (medium severity). Touching the leaves can irritate skin. ^{NC State Extension}

For petsNot well documented

We couldn't find an ASPCA entry for this orchid. (ASPCA's "lady slipper" page covers Impatiens, a different plant.)

🌿 Never eat a wild plant unless you're certain of its ID; this isn't medical advice. Worried about a person? Call Poison Control at 1-800-222-1222. Worried about a pet? Call your vet.

Where does it grow?

USDA PLANTS records pink lady's slipper in 25 states plus Washington, D.C.

AKMEVTNHWAIDMTNDMNILWIMINYRIMAORNVWYSDIAINOHPANJCTCAUTCONEMOKYWVVAMDDEAZNMKSARTNNCSCDCOKLAMSALGAHITXFL

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

Alabama, Connecticut, Delaware, Georgia, Illinois, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, West Virginia, Wisconsin; District of Columbia.

Massachusetts counties with USDA records: Barnstable, Berkshire, Bristol, Dukes, Essex, Franklin, Hampden, Hampshire, Middlesex, Nantucket, Norfolk, Plymouth, Suffolk, Worcester.

New Hampshire counties with USDA records: Belknap, Carroll, Cheshire, Coos, Grafton, Hillsborough, Merrimack, Rockingham, Strafford, Sullivan.

New York counties with USDA records: Albany, Allegany, Bronx, Broome, Cattaraugus, Cayuga, Chautauqua, Chemung, Chenango, Clinton, Columbia, Cortland, Delaware, Dutchess, Erie, Essex, Franklin, Fulton, Genesee, Hamilton, Herkimer, Jefferson, Kings, Lewis, Madison, Monroe, Nassau, Oneida, Onondaga, Ontario, Orange, Oswego, Otsego, Putnam, Queens, Rensselaer, Richmond, Rockland, Saratoga, Schenectady, Schuyler, St. Lawrence, Steuben, Suffolk, Sullivan, Tioga, Tompkins, Ulster, Warren, Washington, Wayne, Westchester, Wyoming.

Names, range and relatives

Native status by region (USDA PLANTS): Canada: Native; Lower 48 states: Native; St. Pierre and Miquelon: Native.

Other scientific names (synonyms in USDA PLANTS): Cypripedium hirsutum, Fissipes acaulis, Fissipes hirsuta.

County records: USDA PLANTS lists it in 647 counties across 25 states; the most are in Virginia (97), Michigan (65), Pennsylvania (60).

Other Cypripedium on Bloomipedia (3): Yellow lady's slipper, Showy lady's slipper, Mountain lady's-slipper.

More from the Orchidaceae family (23 on Bloomipedia; most observed first): Crane-fly orchid, Downy rattlesnake plantain, Broad-leaved helleborine, Western rattlesnake plantain, Spotted coralroot, Showy orchis, Putty root, White bog orchid.

More Massachusetts flowers

Downy rattlesnake plantain

Goodyera pubescens

Native

🌼 Blooms in MA: July–August

Checkered rattlesnake plantain

Goodyera tesselata

Native

🌼 Few flowering records in MA

Roses (genus Rosa)

Rosa

★ NY state flower🌷 Garden flower

🌼 Blooms in MA: May–July

Sources

USDA, NRCS. PLANTS Database, profile CYAC3.
iNaturalist, Cypripedium acaule: taxonomy, research-grade observation counts and “Flowering” annotations, retrieved October 17, 2026.
Wikipedia, Cypripedium acaule (facts restated in our own words).
N.H. RSA 3:17: New Hampshire state wildflower.
State rare and invasive plant lists (34):
Show all 34 state lists
- Massachusetts: Massachusetts Endangered Species Act list (321 CMR 10.90).
- Massachusetts: Massachusetts Prohibited Plant List (MDAR) (Text from MDAR's 2023 scientific-name PDF (mass.gov blocks automated downloads); 2024-2026 additions listed on the mass.gov page: Alnus glutinosa, Pyrus calleryana, Miscanthus sinensis, Aralia elata, Rhodotypos scandens, Symplocos paniculata.).
- New Hampshire: New Hampshire Official Rare Plants List (Ncr 312, eff. Jan 1, 2020).
- New Hampshire: NH Prohibited Invasive Species List (Agr 3800, Table 3800.1).
- New York: New York protected native plants (6 NYCRR § 193.3).
- New York: New York prohibited and regulated invasive species (6 NYCRR Part 575).
- Maine: Maine Rare Plant List (Maine Natural Areas Program, 2021). E and T are Maine's official endangered and threatened plants (12 M.R.S.); SC and PE are tracking categories.
- Maine: Maine Do Not Sell invasive plant list (01-001 C.M.R. ch. 273).
- Michigan: Michigan endangered and threatened plants (Mich. Admin. Code R 299.1028, eff. March 20, 2023).
- Michigan: Michigan prohibited and restricted species (NREPA Part 413 and the 2026 Invasive Species Order), as listed by Michigan's Invasive Species Program.
- Virginia: Virginia endangered and threatened plant and insect species (2VAC5-320-10).
- Virginia: Virginia noxious weeds (2VAC5-317-20, Tier 1, 2 and 3).
- North Carolina: North Carolina Protected Plant Species List (02 NCAC 48F .0301).
- North Carolina: North Carolina Noxious Weed List (02 NCAC 48A .1702) (the list names any non-native Lythrum; we apply it to purple loosestrife (Lythrum salicaria), which isn't native).
- Pennsylvania: Pennsylvania classified native plants (17 Pa. Code Ch. 45, Subchapter B, as amended 2023).
- Pennsylvania: Pennsylvania Noxious Weed List (3 Pa.C.S. § 1519, PA Dept. of Agriculture) (PDA's page spells garlic mustard “Allaria petiolata”; we match it as Alliaria petiolata).
- Vermont: Endangered and Threatened Plants of Vermont (10 V.S.A. chap. 123; list of Feb 10, 2022).
- Vermont: Vermont Quarantine List, Regulated Introduced Plant Species Rule (eff. June 16, 2026).
- Maryland: Maryland threatened and endangered plants (COMAR 08.03.08.05, .06 and .08).
- Maryland: Maryland Prohibited Invasive Plant List (COMAR 15.06.04.06; MDA, updated July 2026).
- Tennessee: Tennessee endangered plants (Tenn. Comp. R. & Regs. 0400-06-02-.04, Rare Plant Protection and Conservation Act).
- Tennessee: Tennessee Pest Plant List (Tenn. Comp. R. & Regs. 0080-06-24-.02).
- New Jersey: New Jersey Endangered Plant Species List (N.J.A.C. 7:5C-5.1).
- New Jersey: New Jersey prohibited invasive plant species (Invasive Species Management Act; propagation banned from Jan 1, 2027, sale from Jan 1, 2030).
- Wisconsin: Wisconsin endangered and threatened species list (Wis. Admin. Code NR 27.03).
- Wisconsin: Wisconsin invasive species rule (Wis. Admin. Code NR 40.04 prohibited, NR 40.05 restricted).
- Connecticut: Connecticut Endangered, Threatened and Special Concern Plants (RCSA 26-306; 2015 list).
- Connecticut: Connecticut prohibited invasive plants (Conn. Gen. Stat. § 22a-381d).
- West Virginia: West Virginia noxious weeds (W. Va. Code R. § 61-14A-5) (the rule abbreviates some names (e.g. “P. cuspidatum”); we expand them to match).
- Kentucky: Kentucky endangered and threatened plant lists (400 KAR 3:040, eff. 2026).
- Kentucky: Kentucky noxious weeds and invasive plants on state rights-of-way (KRS 176.051; species list from the Kentucky Transportation Cabinet).
- Rhode Island: Rhode Island Rare Plants 2016 (RI Natural History Survey, from the RI Wildlife Action Plan; informational, Rhode Island has no state plant-protection listing law).
- Delaware: Rare and Uncommon Plants of Delaware (DNREC, 2024; informational, Delaware has no state plant-protection list).
- Delaware: Delaware Invasive Plant List (3 Del. Admin. Code § 806-3.0).
USFWS, ECOS species database (ESA listing check), October 17, 2026.
NatureServe Explorer, Cypripedium acaule (global and state ranks).
Edibility and toxicity: NC State Extension.
Photo: Shirley Zundell via iNaturalist · CC BY 4.0 · resized.