Bloomipedia
Purple loosestrife (Lythrum salicaria)
Photo: Duarte Frade via iNaturalist · CC BY 4.0 · resized

Flower profile

Purple loosestrife

Lythrum salicaria

Introduced in the lower 48

Purple loosestrife is a wildflower that USDA PLANTS lists as introduced in the lower 48 states. It's on our flower lists for 18 states, and across the U.S. it's most often seen in bloom in July–September.

43states
18of our state lists
47,019U.S. sightings*

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

On our lists for: Connecticut, Delaware, Idaho, Illinois, Indiana, Maine, Massachusetts, Michigan, Minnesota, Nebraska, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, Vermont, Wisconsin

🚫
Regulated invasive plant in New York, Massachusetts, Michigan, Pennsylvania, Ohio, Illinois, New Jersey, Minnesota, Vermont, Wisconsin, Maine, Connecticut, Idaho, Delaware and Nebraska. It's on those states' official invasive plant lists (New York: Prohibited invasive species (6 NYCRR § 575.3); Massachusetts: Prohibited plant (sale, import and propagation banned); Michigan: Restricted invasive species; Pennsylvania: Class B noxious weed; Ohio: Invasive plant (sale and propagation prohibited); Illinois: Exotic weed (sale and planting prohibited); New Jersey: Prohibited invasive plant (propagation banned from 2027, sale from 2030); Minnesota: Prohibited noxious weed (control); Vermont: Quarantine List, Tier 3; Wisconsin: Restricted invasive species; Maine: Do Not Sell invasive plant (illegal to sell or import); Connecticut: Prohibited invasive plant (some listings take effect on later dates; see the statute); Idaho: Statewide containment noxious weed; Delaware: Invasive Plant List (sale and propagation prohibited); Nebraska: Noxious weed (landowners must control it)). Please don't plant or share it there. 6 NYCRR Part 575 MA Prohibited Plant List MI prohibited/restricted list PA noxious weed list OAC 901:5-30-01 17 IAC 1100.30 NJ prohibited invasive list MN noxious weed list Vermont Quarantine List NR 40 Maine Do Not Sell list CGS § 22a-381d IDAPA 02.06.09 3 DE Admin. Code 806 25 NAC 10-001.02

Quick look

Lythrum salicaria or purple-loosestrife is a flowering plant belonging to the family Lythraceae. It should not be confused with other plants sharing the name loosestrife that are members of the genus Lysimachia in the family Primulaceae. This herbaceous perennial plant is native to temperate regions of Europe, Asia, northern Africa, and eastern Australia.

  • It belongs to the Lythraceae family. iNaturalist
  • USDA PLANTS describes it as an herb (forb) / a subshrub with a perennial life cycle. USDA PLANTS
  • USDA PLANTS lists it as introduced in the lower 48 states and records it in 43 states. USDA PLANTS
  • In New York, most iNaturalist sightings of it in flower come in July–September. iNaturalist
  • In Massachusetts, most iNaturalist sightings of it in flower come in July–September. iNaturalist
  • iNaturalist has 7,427 research-grade sightings of it in New York, ranking #18 among the 109 flowers on our New York list. iNaturalist
  • iNaturalist has 5,832 research-grade sightings of it in Massachusetts, ranking #18 among the 110 flowers on our Massachusetts list. iNaturalist
  • iNaturalist has 4,512 research-grade sightings of it in Michigan, ranking #16 among the 111 flowers on our Michigan list. iNaturalist

State flower gift ideas

This one is a regulated invasive plant, so here are state flower gifts instead.

When does it bloom?

Flowering records by month across the U.S. (iNaturalist research-grade observations marked “Flowering”) (6,354 records)
Bloom time in each of our 18 states
StateTypePeak bloomSightings*
New YorkIntroducedJuly–September7,427
MassachusettsIntroducedJuly–September5,832
MichiganIntroducedJuly–September4,512
PennsylvaniaIntroducedJuly–September3,654
OhioIntroducedJune–September3,066
IllinoisIntroducedJune–September2,531
New JerseyIntroducedJuly–September2,434
MinnesotaIntroducedJuly–September2,154
VermontIntroducedJuly–September2,047
WisconsinIntroducedJuly–September1,686
MaineIntroducedJuly–September1,372
New HampshireIntroducedJuly–September1,233
ConnecticutIntroducedJuly–September1,113
IndianaIntroducedJuly–September877
IdahoIntroducedJune–September438
Rhode IslandIntroducedJuly–October359
DelawareIntroducedJuly–September231
NebraskaIntroducedfew records177

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
New York
Not listed Not on New York protected native plants (6 NYCRR § 193.3). NatureServe: SNA, not applicable (usually because it isn't native there) in New York. 6 NYCRR § 193.3
Massachusetts
Not listed Not on Massachusetts Endangered Species Act list (321 CMR 10.90). NatureServe: SNA, not applicable (usually because it isn't native there) in Massachusetts. MESA list
Michigan
Not listed Not on Michigan endangered and threatened plants (Mich. Admin. Code R 299.1028, eff. March 20, 2023). NatureServe: SNA, not applicable (usually because it isn't native there) in Michigan. R 299.1028
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
Ohio
Not listed Not on Ohio endangered and threatened plants (Ohio Adm. Code 1501:18-1-03, eff. Dec. 26, 2024). NatureServe: SNA, not applicable (usually because it isn't native there) in Ohio. OAC 1501:18-1-03
Illinois
Not listed Not on Illinois List of Endangered and Threatened Flora (17 Ill. Adm. Code 1050), per the Endangered Species Protection Board's 2025 checklist. NatureServe: SNA, not applicable (usually because it isn't native there) in Illinois. IL E&T checklist 2025
New Jersey
Not listed Not on New Jersey Endangered Plant Species List (N.J.A.C. 7:5C-5.1). NatureServe: SNA, not applicable (usually because it isn't native there) in New Jersey. N.J.A.C. 7:5C-5.1
Minnesota
Not listed Not on Minnesota endangered, threatened and special concern plants (Minn. R. 6134.0300). NatureServe: SNA, not applicable (usually because it isn't native there) in Minnesota. Minn. R. 6134.0300
Vermont
Not listed Not on Endangered and Threatened Plants of Vermont (10 V.S.A. chap. 123; list of Feb 10, 2022). NatureServe: SNA, not applicable (usually because it isn't native there) in Vermont. Vermont E&T list
Wisconsin
Not listed Not on Wisconsin endangered and threatened species list (Wis. Admin. Code NR 27.03). NatureServe: SNA, not applicable (usually because it isn't native there) in Wisconsin. NR 27.03
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: SNA, not applicable (usually because it isn't native there) in Maine. Maine rare plant list
New Hampshire
Not listed Not on New Hampshire Official Rare Plants List (Ncr 312, eff. Jan 1, 2020). NatureServe: SNA, not applicable (usually because it isn't native there) in New Hampshire. NH Ncr 312
Connecticut
Not listed Not on Connecticut Endangered, Threatened and Special Concern Plants (RCSA 26-306; 2015 list). NatureServe: SNA, not applicable (usually because it isn't native there) in Connecticut. CT E/T/SC list
Indiana
No list Indiana has no state law listing endangered or threatened plants (the DNR keeps a rare plant list, but it isn't regulatory), so we show NatureServe's Indiana ranks instead. NatureServe: SNA, not applicable (usually because it isn't native there) in Indiana.
Idaho
No list Idaho has no state law listing endangered or threatened plants, so we show NatureServe's Idaho ranks instead. NatureServe: SNA, not applicable (usually because it isn't native there) in Idaho.
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: SNA, not applicable (usually because it isn't native there) 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: SNA, not applicable (usually because it isn't native there) in Delaware. DE rare plants 2024
Nebraska
Not listed Not on Nebraska threatened and endangered species (163 Neb. Admin. Code ch. 4, § 004). NatureServe: SNA, not applicable (usually because it isn't native there) in Nebraska. 163 NAC 4-004
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 peopleNot well documented

None of the sources we checked (NC State Extension (no edibility or poison notes on its page), USDA PLANTS) say whether it's edible or poisonous for people. NC State Extension

For petsNot well documented

It isn't on the ASPCA plant list, and NC State Extension doesn't flag it for pets.

🌿 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 purple loosestrife 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, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming; District of Columbia.

New York counties with USDA records: Albany, Bronx, Cayuga, Chautauqua, Chenango, Clinton, Columbia, Delaware, Dutchess, Erie, Essex, Greene, Kings, Livingston, Madison, Monroe, Nassau, Niagara, Oneida, Onondaga, Orange, Oswego, Putnam, Queens, Rensselaer, Richmond, Rockland, Saratoga, St. Lawrence, Suffolk, Sullivan, Tompkins, Ulster, Warren, Washington, Westchester.

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

Michigan counties with USDA records: Allegan, Alpena, Antrim, Barry, Bay, Benzie, Berrien, Calhoun, Cass, Cheboygan, Chippewa, Clinton, Delta, Eaton, Emmet, Hillsdale, Houghton, Huron, Ingham, Iosco, Kalamazoo, Keweenaw, Leelanau, Lenawee, Livingston, Mackinac, Macomb, Monroe, Muskegon, Newaygo, Oakland, Ottawa, Presque Isle, Saginaw, Schoolcraft, Shiawassee, St. Clair, Washtenaw, Wayne.

More New York flowers

Sources