The showy purple spikes of purple loosestrife are attractive in the garden and along roadsides, but the plant’s rampant spread has greatly reduced the ecological value of marshes by displacing native wetland vegetation such as cattails ( Typha spp.) that wildlife uses as food or shelter. One mature plant can produce over 2 million seeds a year that are easily transported by the wind or water into wetlands. The seeds easily germinate, and no natural predator holds this plant in check. Even cultivars reported to be sterile can produce highly fertile seed if grown with other cultivars or wild loosestrife.
Noteworthy CharacteristicsShowy purple flower spikes. Highly invasive in all regions.
CareGrows in any moist soil in full sun.
PropagationSelf-sows with abandon.
ProblemsSlugs, snails, Japanese beetles.
- Genus : Lythrum
- Plant Width : 1 to 3 feet
- Plant Height : 3 to 6 feet
- Zones : 4, 5, 6, 7, 8, 9
- Bloom Time : Fall, Summer
- Growth Rate : Fast
- Light : Full Sun
- Moisture : Medium to Wet
- Maintenance : Moderate
- Plant Type : Perennials
- Flower Color : Pink
- Plant Seasonal Interest : Summer Interest
Plant Characteristics are only available to Fine Gardening members
Sign up for a free trial and get instant access to our complete plant guide as well as our entire collection of articles and videos.