Bloomipedia
Bitter wintercress (Barbarea vulgaris)
Photo: Sandy Wolkenberg via iNaturalist · CC BY 4.0 · resized

Flower profile

Bitter wintercress

Barbarea vulgaris

Bitter wintercress (Barbarea vulgaris) is a flowering plant in the Brassicaceae family, introduced in the lower 48 states, blooming mostly April–May across the U.S.

Not native to Pennsylvania

Bitter wintercress is a wildflower that USDA PLANTS lists as introduced in the lower 48 states. In Pennsylvania it's most often seen in bloom in April–May.

43states where USDA records it
2,557PA sightings*
14,192U.S. sightings*

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

On our lists for: Pennsylvania

Quick look

Barbarea vulgaris, called wintercress, or alternatively winter rocket, rocketcress, yellow rocketcress, yellow rocket, wound rocket, herb barbara, creases, or creasy greens, is a biennial herb of the genus Barbarea, belonging to the family Brassicaceae.

  • It belongs to the Brassicaceae family. iNaturalist
  • USDA PLANTS describes it as an herb (forb) with a biennial life cycle. USDA PLANTS
  • USDA PLANTS lists it as introduced in the lower 48 states and records it in 43 states. USDA PLANTS
  • NatureServe lists it as not native to Pennsylvania. NatureServe
  • In Pennsylvania, most iNaturalist sightings of it in flower come in April–May. iNaturalist
  • iNaturalist has 2,557 research-grade sightings of it in Pennsylvania, ranking #83 among the 190 flowers on our Pennsylvania list. iNaturalist

When does it bloom?

In Pennsylvania, most flowering sightings come in April–May.

Flowering records by month in Pennsylvania (iNaturalist research-grade observations marked “Flowering”) (180 records)

Conservation status

Federal (U.S. ESA)
Not listed No U.S. Endangered Species Act listing in the USFWS ECOS database. USFWS ECOS
NatureServe global
GNR Not yet ranked worldwide. NatureServe
Pennsylvania
Not listed Not on Pennsylvania classified native plants (17 Pa. Code Ch. 45, Subchapter B, as amended 2023). NatureServe: SNA, not applicable (usually because it isn't native there) in Pennsylvania. 17 Pa. Code Ch. 45
Rare elsewhere
No other U.S. state ranks it S1, S2, SH or SX.

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

Can you eat it?

For peopleCaution: partly edible, partly poisonous

NC State Extension lists it as poisonous to humans (severity: low). Poisonous parts: leaves. Symptoms they list: “Consuming quantities of leaves can affect kidney function.” They also note: “Young leaves can be eaten raw or cooked, but there is some evidence that it can impact kidney function.” NC State Extension

For petsToxic to horses (not dogs or cats)

ASPCA's entry “Yellowrocket” (Barbarea vulgaris) lists it as toxic to horses, but non-toxic to dogs and cats. Signs include: Gastrointestinal irritation, colic Credit: Robert H. Mohlenbrock @ USDA-NRCS PLANTS Database / USDA SCS. 1989. Midwest wetland flora: Field office illustrated guide to plant species. Midwest National… ASPCA

🌿 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 bitter wintercress in 43 states plus Washington, D.C.

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

Alabama, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Montana, Nebraska, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming; District of Columbia.

Pennsylvania counties with USDA records: Adams, Allegheny, Armstrong, Beaver, Bedford, Berks, Blair, Bradford, Bucks, Butler, Cambria, Cameron, Carbon, Centre, Chester, Clarion, Clearfield, Clinton, Columbia, Crawford, Cumberland, Dauphin, Delaware, Elk, Erie, Fayette, Forest, Franklin, Fulton, Greene, Huntingdon, Indiana, Jefferson, Juniata, Lackawanna, Lancaster, Lawrence, Lebanon, Lehigh, Luzerne, Lycoming, McKean, Mercer, Mifflin, Monroe, Montgomery, Montour, Northampton, Northumberland, Perry, Philadelphia, Pike, Potter, Schuylkill, Snyder, Somerset, Sullivan, Susquehanna, Tioga, Union, Venango, Warren, Washington, Wayne, Westmoreland, York.

Names, range and relatives

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

Other scientific names (synonyms in USDA PLANTS): Barbarea arcuata, Campe barbarea.

County records: USDA PLANTS lists it in 1146 counties across 40 states; the most are in Missouri (109), Illinois (87), Ohio (80).

More from the Brassicaceae family (24 on Bloomipedia; most observed first): Garlic mustard, Dame's rocket, Cut-leaved toothwort, Wild radish, Milkmaids, Annual honesty, Western wallflower, Hoary alyssum.

More Pennsylvania flowers

Garlic mustard (Alliaria petiolata)

Garlic mustard

Alliaria petiolata

Introduced

🌼 Blooms in PA: April–May
Dame's rocket (Hesperis matronalis)

Dame's rocket

Hesperis matronalis

Introduced

🌼 Blooms in PA: May–June
Cut-leaved toothwort (Cardamine concatenata)

Cut-leaved toothwort

Cardamine concatenata

Native

🌼 Blooms in PA: March–April

Sources