Gardening Questions And Answers
Origin and Spread 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.
Native to central Europe and Turkey, this plant is easy to grow and excellent at providing fast-spreading cover when required, creating great visual impact. However, attention should be paid to controlling its spread as this plant tends to be invasive. Vigorous, this rhizomatous perennial reaches 36 in.
Yellow loosestrife grows quickly and easily, but planting in pots can help control this. This plant is a perennial and can survive winters in USDA hardiness zones 4-8. Blooming typically occurs from June through September, and this plant’s yellow blooms are a beautiful ornamental addition to gardens.
If late- emerging purple loosestrife seedlings survive the winter, new or expanding popula- tions of purple loosestrife will result. However, 37% of purple loosestrife seed- lings that emerged in late August, although stunted, generated a crown that was able to overwinter successfully and regrow the following spring.
Since it was brought to North America, purple loosestrife has become a serious invader of wetlands, roadsides and disturbed areas. The plant forms dense stands with thick mats of roots that can extend over vast areas. The stands reduce nutrients and space for native plants and degrade habitat for wildlife.
Purple loosestrife negatively affects both wildlife and agriculture. It displaces and replaces native flora and fauna, eliminating food, nesting and shelter for wildlife. Purple loosestrife forms a single-species stand that no bird, mammal, or fish depends upon, and germinates faster than many native wetland species.