Purple Loosestrife

Lythrum salicaria

Family: Lythraceae (ly-THRAY-see-ee) (Info)
Genus: Lythrum (LY-thrum) (Info)
Species: salicaria (sa-lih-KAR-ee-uh) (Info)



Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Requires consistently moist soil; do not let dry out between waterings

Where to Grow:

Unknown - Tell us


24-36 in. (60-90 cm)

36-48 in. (90-120 cm)

4-6 ft. (1.2-1.8 m)


4-6 ft. (1.2-1.8 m)


USDA Zone 3a: to -39.9 C (-40 F)

USDA Zone 3b: to -37.2 C (-35 F)

USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Full Sun



Bloom Color:


Magenta (Pink-Purple)

Bloom Time:

Mid Summer

Late Summer/Early Fall



Other details:

May be a noxious weed or invasive

Soil pH requirements:

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

7.9 to 8.5 (alkaline)

Patent Information:


Propagation Methods:

By dividing the rootball

By dividing rhizomes, tubers, corms or bulbs (including offsets)

From seed; direct sow outdoors in fall

From seed; winter sow in vented containers, coldframe or unheated greenhouse

From seed; stratify if sowing indoors

From seed; sow indoors before last frost

From seed; direct sow after last frost

From seed; germinate in a damp paper towel

Self-sows freely; deadhead if you do not want volunteer seedlings next season

Seed Collecting:

Allow seedheads to dry on plants; remove and collect seeds


This plant has been said to grow in the following regions:

Ward, Arkansas

Woodland Park, Colorado

Broad Brook, Connecticut

Edinburg, Illinois

Pekin, Illinois

Nichols, Iowa

Barbourville, Kentucky

Calvert City, Kentucky

Belle Chasse, Louisiana

Pikesville, Maryland

Georgetown, Massachusetts

Milton, Massachusetts

Belleville, Michigan

Erie, Michigan

Grand Rapids, Michigan

Saint Helen, Michigan

Saint Paul, Minnesota

Springfield, Missouri

Croton On Hudson, New York

Glen Head, New York

Ithaca, New York

Southold, New York

Belfield, North Dakota

Fargo, North Dakota

Glouster, Ohio

Lancaster, Ohio

Twinsburg, Ohio

Salem, Oregon

Mercer, Pennsylvania

Millersburg, Pennsylvania

Schwenksville, Pennsylvania

show all

Gardeners' Notes:


On Aug 3, 2014, coriaceous from ROSLINDALE, MA wrote:

Those who wish to grow this handsome but ecologically damaging plant in North America might consider growing our showy native winged loosestrife (Lythrum alatum) instead. The two plants look similar and are similarly long blooming.


On Aug 17, 2011, gsteinbe from Trenton, NJ wrote:

People shouldn't jump to conclusions about plants that they see and think that they have identified properly. There's a native species of Loosestrife (Winged Loosestrife, Lythrum alatum), which is endangered. It looks pretty much exactly like the invasive Purple Loosestrife, but its stems are "winged" (like the plant in the photo at http://www.aphotoflora.com/images/hypericaceae/hypericum_und...). So, if you run out and start ripping up "Purple Loosestrife" in the wild, keep in mind that you may be ripping out its native, endangered cousin. And if you see "Purple Loosestrife" in someone's garden, don't be too quick to jud... read more


On Jul 13, 2011, MarilynJL from Champaign, IL wrote:

Purple loosestrife (Lythrum salicaria) is listed as a noxious weed in nearly every state in the U.S, and is therefore illegal to sell, buy, trade or transport. It infests waterways across the entire continental U.S. (with the exception of Florida below the panhandle) and Canada below the Arctic Circle. Lythrum salicaria outcompetes native native plants. It degrades natural habitat and changes composition and flow of waterways. One plant is capable of annually producing millions of viable seeds. It also
reproduces from rootstock, one rootstock being capable of producing 30 to 50 new plants.

The reason it is not a problem in Europe is that it evolved with its natural restraints -- insects & birds that will feed on it and other plants native to Europe that can compe... read more


On Mar 14, 2011, WhiteflowerEU from St.Gallen
Switzerland wrote:

I'm really shocked about the number of negative comments to this plant - here in Europe, as well as in other parts of the world (Asia, Africa, Australia, etc.), it is a native plant, and hybrids/ sorts are not invasive at all. And it has not only decorative but also medicinal and technical uses.
If you do not want it to spread - just cut off the spent flower heads timely, what's the problem? Then no wind or bird, or whatever, will carry it away. If you cannot be responsible enough - then yes, better not to plant it in your garden.
The problem is not with the plant itself but with the human attitude, IMHO.
The best and most reasonable comment is that one of gregr18. Don't like hysterias of any kind.


On Jul 18, 2009, 4evrMoi from Lancaster, OH wrote:

I agree with gregr18 who posted in October '05.

I have this perennial and know others in this area (Lancaster, OH) who also have it, and not one of us have experienced its so-called, "invasive" out-of-control nature. Apparently from what I'm reading here, those who have "problems" with it are in "wetland" areas.

Its beauty and benefits for bees and Hummers far outweigh the negative qualities it supposedly posesses.

Q: IF it's "banned" in so many states, then "why" do greenhouses and/or nurseries sell it ?


On Jul 13, 2009, sdlugo from Downers Grove, IL wrote:

I find it difficult to swallow what I am reading on this site. The plant kills off native plants, which in turn kills off native animals including fish, turtles, and frogs. The seeds spread easily over far distances, so even if you think there's nothing around it can affect, there most certainly is.
Whether or not you think this is ok, the government does not. Therefore you are spending your tax money and mine getting rid of this plant in the wild.
So even if you are not interested in conservation and being a good steward to the environment then know that it is affecting you in the pocketbook. There are too many good, native options that are beautiful and beneficial to even consider something as destructive as Purple Loosestrife. Please do not plant it and do not think of it... read more


On Mar 8, 2009, giftgas from Everson, WA (Zone 7b) wrote:

I love this plant...it grows great in a 5 gallon pot indoors. I don't live in a bog, so I don't worry about it; invasive is a silly word.


On Nov 3, 2007, distantkin from Saint Cloud, MN (Zone 4b) wrote:

I saw this plant in a book and thought it was very pretty, then I looked on the MN DNR and found this...
"Purple loosestrife (Lythrum salicaria, L. virgatum and any combination thereof) is listed as a noxious weed and a prohibited exotic species in Minnesota. It is illegal to possess, plant, transport, or sell purple loosestrife in Minnesota. "
So, as addicted as I am to plants and collecting them...this is one I will have to pass on.


On Aug 26, 2007, phantomasc from Georgetown, MA wrote:

Based upon observation over the years, this plant does NOT eradicate cat tails or other wetland plants. It attracts both honey bees and bumble bees. It is gorgeous where plant heavily populates. Set aside the invasive hysteria this plant generates, and enjoy it along with the bees.

Survives winter road salt to return each year in my yard by the roadway.


On Aug 5, 2007, fishlore from Wolfeboro, NH wrote:

This beauty has spread up into New Hampshire from Massachusetts, where it entered in wool imported from Britain. It is so beautiful that I can't resist its evil charm. Mixed with tiger lillies it is spectacular and hasn't crowded mine out at all.


On Jul 23, 2007, eden100 from Edinburg, IL (Zone 6a) wrote:

I bought one from Lowe's last year and was worried about its reputation of being extremely invasive, however it turned out to be one of my favorite perennials. I bought another purple one this year and two golden alexander loosestrife. I see this plant all over town and it is popular in commercial landscape. It doesn't seem to spread at all. I find amenomes far more invasive!


On Jul 13, 2007, claypa from West Pottsgrove, PA (Zone 6b) wrote:

It is illegal to sell, propagate, or transport this plant, including all its cultivars, in Pennsylvania. Yet, it's growing all over the place.


On Apr 1, 2007, Joan from Belfield, ND (Zone 4a) wrote:

This plant is listed on the North Dakota invasive/troublesome list and this information is being distributed in a guide developed by the ND Weed Control Association and other agencies.

Plant Features
Perennial, 3 to 8 feet tall
Flower clusters rose-purple on elongated spikes
Flowers 4 to 6 petals
Stems 5 to 6 sided, emerge from taproot
More mature (older) plants have a large woody crowned taproot with many stems
Many small seeds in brown capsules
Blooms from July through August
Leaves opposite and/or whorled on sttem
Spreads by roots, seeds, and stem fragments

Widespread invasive found in gardens and escaped into moist-marshy areas. Forms dense monotypic stands de... read more


On Dec 27, 2006, frostweed from Josephine, Arlington, TX (Zone 8a) wrote:

Purple Loosestrife Lythrum salicaria is Naturalized in Texas and other States and is considered an invasive and noxious plant in Texas.


On Sep 7, 2006, NJChickadee from Egg Harbor Township, NJ wrote:

The problem with this beautiful plant is that it is very invasive, crowding out native plants. Even supposedly sterile varieties can become fertile and millions of dollars are spent eradicating Loosestrife from natural preserves. Anise Hysop is a nice alternative.


On May 26, 2006, RyanUWRF from Cameron, WI wrote:

It is INVASIVE!!!! That is all that has to be said. I work with Purple Loosestrife on a daily basis, because it is my job to get rid of it in the wild. By law it is illegal to grow it in the State of Wisconsin!!


On Mar 16, 2006, billyporter from Nichols, IA (Zone 5a) wrote:

A neighbor gave me a start. We don't live near water, but it makes me uncomfortable to grow it, knowing what it does. Some plants are so pretty we can't resist, but we should, if care about nature.


On Feb 5, 2006, Gabrielle from (Zone 5a) wrote:

This is an illegal species in Illinois. Even though it wasn't spreading in my yard, I tore it all out.


On Oct 1, 2005, gregr18 from Bridgewater, MA (Zone 6b) wrote:

A beautiful marginal plant that has unjustifiably become a favorite scapegoat of the so-called "bioinvasionists".

This plant doesn't destroy ecologies, it changes them. Despite the protestations of a vocal minority, ecologies are not fixed entities. Changes in ecologies, whether facilitated by humans or not, are inevitable. Ice Age(s), anyone? With that in mind, this plant has become integrated into many, usually heavily disturbed, biota, does not form monocultures, and does not create "ecological deserts". Its conspicuous blooms, instead of being appreciated, have become a signal of an ecological disaster that simply does not exist.

Purple Loosestife is highly opportunistic, and mainly flourishes in areas in which human activity has created a niche f... read more


On Sep 2, 2005, pirl from (Arlene) Southold, NY (Zone 7a) wrote:

Very invasive. Takes over entire areas and deprives my daylilies of their share of sunshine and water. We remove them and destroy them on sight. It's a fast grower so it can escape notice for awhile.

Connecticut has also added it to their prohibited list.


On Aug 15, 2005, westocast73 from (Zone 1) wrote:

lmelling - This plant is not native to North America and is not a Native North American Wildflower. Please do not spread mis-information about a very invasive weed that is destroying habitat for native wetland plants and the animals that rely on them. I know when you see a pretty flower such as this growing wild it is hard to imagine how it can be a bad thing but it is. It will take away valuable land space for native wetland plants and thus the food sources for many wetland animals especially ducks who can not digest Loosestrife and are loosing their native food sources to it. This plant was mistakenly brought over in the 1800's from Eurasia and has been spreading ever since. Please do not grow this plant as you will surely be causing ecological problems that you may not see but are deffi... read more


On Aug 14, 2005, Equilibrium wrote:

Hideously invasive and so are the cultivars which are being released in record numbers. If I could be afforded the luxury of having just five species eradicated from the continent of North America, this would be one of them.

Hybrids, cultivars, and seeds are available on the Internet. Please do not purchase this plant or any of its hybrids or cultivars. Please do not share seeds of this plant or any of its hybrids or cultivars. Please do not share the plants themselves. Please try your best to control this beast that escaped cultivation and is destroying one ecosystem after the next.

eiting to add-
Purple Loosestrife is at home in both freshwater as well as brackish environments. This plant reproduces both vegetatively and sexually. At maturity, one s... read more


On Jul 12, 2005, kc8lcw from Columbus, OH (Zone 6a) wrote:

This plant may be classified as a prohibited noxious weed in Ohio, but I have had it growing in my yard for 4 years now and it has not invaded the rest of my garden. It is planted in a bed behind my little 90 gal preform pond and has behaved itself quite well. The area where it is planted stays mainly damp due to poor drainage, and I have not had a problem with it so far.


On Jul 5, 2005, designart from Schwenksville, PA (Zone 6a) wrote:

Thank you everyone for such great information. I also believed that the sterile cultivars may be acceptable to use, but after reading your comments, I will certainlly not be using any of the cultivars!!!


On Dec 23, 2004, nutrility21 from San Antonio, TX wrote:

> Medicinal uses: Treated diarrhoea, constipation, dysentry,
vaginal discharge, fever, lung and liver complaints, infant
cholera, wounds, sores, eye and throat infections, glandular
diseases. Dye: Unmordented yarn, flower tops with iron added made a deep black. Other uses: Tannin rich stems used intanning leather.
> ( I found this information on a site about old norse, it
must have been a plant native to scandinavia. Not positive
how to use for treatment, common sence says small amounts
inested fresh or brewed for internal problems,
compress for external problems.)


On Nov 25, 2004, caron from Woodland Park, CO (Zone 4b) wrote:

Colorado Class A Noxious Weed. Mandatory eradication.
All locations of this plant in Colorado should be immediately reported to the Colorado Department of Agriculture.


On Nov 13, 2004, lmelling from Ithaca, NY (Zone 5b) wrote:

The wild form of this used to grow in ditches and moist fields here in the fingerlakes region of central NY state. However, over the past 5 years, the state has taken serious measures to eradicate it due to it's invasive habit - and unfortuanately (in our estimation) have been more than successful.

Members of our dried flower booth used to cut and dry this native wildflower for use in arrangements and dried bouquets, and it was very beautiful in such. However, with the eradication nearly complete it is much harder to find this beautiful plant and those that you do no longer dry as well due probably to the methods of eradication (microbes or insects - I'm not sure which). Sad to see such a beautiful wildflower almost totally eliminated!


On Nov 12, 2004, cherishlife from Pocola, OK (Zone 7a) wrote:

Some people are just not "getting it" as to HOW this plant in invasive. It is not necessarily invasive in your own yard, but the seeds are spread far and wide into the wetlands and that is the problem. The list of states that have this plant listed as a noxious weed is growing very quickly.

As of right now, the USDA has these states listed:

Alabama - Class B noxious weed
Arizona - Prohibited noxious weed
Arkansas - Noxious weed
California - B list (noxious weeds)
Colorado - Noxious weed
Florida - Prohibited aquatic plant, Class 1
Idaho - Noxious weed
Indiana - Permit required
Iowa - Secondary noxious weed
Michigan - Sale prohibited
Minnesota - Prohibited noxious weed
Mis... read more


On Jun 22, 2004, Rarri from Glen Head, NY (Zone 7a) wrote:

Wow, everyone hates this plant.. not me.. IT GROWS in my yard I wish it would spread, but it doesn't.. It gets lots of sun, and not a tremendous amount of water .. It is very hardy and colorful and I am happy to see it grow..You guys can drop your overgrowth and my place anytime ha..


On Jan 8, 2004, dupperdog from Superior, WI wrote:

We have had this plant in the wild here for at least 30 years. I can remember looking over a large marsh at that time and seeing the whole thing purple with these flowers in August. It was actually quite beautiful if you were objective. Guess what? We still have wildlife and plenty of native plants in the area. In fact, if you go to the same marsh now, the occurence of purple loosestrife is a lot less than it was at that time. No one has done much releasing of the beetles which are supposed to destroy this plant yet. I tend to doubt reports of the dangers of this plant.


On Jan 8, 2004, Karenn from Mount Prospect, IL (Zone 5a) wrote:

Please be aware that the SEEDS of this plant can be carried far and wide by birds & wind currents; also, the non-native hybrids can REVERT via seed back to the parentage! I believe that Illinois has (or is in process of) banning the sale of ALL varieties of lythrum - hybrid or not! And yes, this plant is indeed crowding out native plants, clogging what used to be flowing waterways, etc. I could not EVER recommend a plant as invasive as this one is - it is on the National registry of invasives!


On Jan 7, 2004, marctain from Montral, QC (Zone 4b) wrote:



On Aug 12, 2003, davecwik from Smiths Creek, MI wrote:

i cannot stand this plant , purple loosestrife is a highly invasive weed that is destroying swampland in michigan becuse people bought it beleving it was "sterile" it turned out to only be sterile until 4 years old when the plant reached maturity and is now a huge problem.if you find it please destroy it.
thank you


On Jul 28, 2003, Gardener4Fun from Sweetwater, TX (Zone 7a) wrote:

According to Cornell University's Horticulture Studies Program (see invasiveplants.net), this weed has been deemed invasive and dangerous to ecology in at least 19 states. It is present in all U.S. states except Florida, Hawaii, and Alaska.

Once established, it persists for decades, is difficult to control using conventional techniques (chemical, physical, and mechanical), and continues to spread into adjacent areas. Plants are long lived and mature plants may produce more than 2.5 million seeds annually, which remain viable for many years. Spread to new areas occurs exclusively by seed, which is transported mainly by water but also adheres to boots, waterfowl and other wetland fauna.

If you have this in your garden, please consider the information posted ab... read more


On Jun 13, 2003, RubyStar from Madison, WI (Zone 5a) wrote:

Beautiful it may be, but this plant (and its cousin, L. virgatum) is deadly to North American wetlands. It is quite out of control, and is listed as a biological invasive in at least 30 U.S. States, banned for sale or growing in at least 14 U.S. States, and banned or regulated in areas of Canada as well. The self-sterile hybrids are not exempt from this status, as they pollinate wild-growing stands and thus contribute hugely to the problem.

Purple Loosestrife doesn't sweep through your garden, taking everything out along the way, it disperses by massive seeding into the wild, particularly into wetlands, and quickly establishes itself and takes over, becoming a monoculture. In addition, hundreds of species of wetland birds, fish, and mammals are seriously impacted by the los... read more


On Apr 14, 2003, lgsherk from Vandiver, AL (Zone 7a) wrote:

Purple Loosestrife is considered invasive in my area and not recommended for planting.It will take over if planted in a wet area.
Linda in Alabama


On May 2, 2002, Lilith from Durham
United Kingdom (Zone 8a) wrote:

An elegant plant with tall spikes of purple flowers. Each plant has one of three sorts of flowers. The style is either shorter than, about equal to, or much longer than the sepals, and the stamens are equally different in length. This ensures that a flower receives pollen from a different plant.