Lythrum virgatum. There are several named cultivars.

this link: https://www.dnr.state.mn.us/invasives/aquaticplants/purpleloosestrife/index.html

says this: Purple loosestrife (Lythrum salicaria, L. virgatum and any combination thereof) is listed as a MDA Prohibited Noxious Weed (Control List) (link is external) and a prohibited invasive species in Minnesota, which means it is unlawful (a misdemeanor) to possess, import, purchase, transport or introduce this species except under a permit for disposal, control, research or education

in addition it says this: Purple loosestrife is native to Europe and Asia. The species was unintentionally introduced to the United States’ Great Lakes through contaminated solid cargo ship ballast as well as through the deliberate importation of seeds. The first discovery in the United States was in Lake Ontario in 1869. Purple loosestrife was sold and planted for decades as a decorative ornamental plant. However, due to its negative impacts on native plants and its ability to escape from cultivation, purple loosestrife is illegal to sell in most states

and many other interesting things ...

you tell us your zone.. which is rather useless... a big city name is usually more helpful.. find out if this is noxious in the state you are in ... or tell us and maybe one of us could google it for you

ken

Thank you guys so very much!! been looking for this for a couple of years now and was in the wrong genus altogether.

Interesting… Lythrum virgatum is actually not allowed for sale in some states or commerical use at all..