- Introduced from Europe and Asia to the Atlantic coast of North America in the early 1800’s.
- Up to 2 meters tall with several stalks covered in pinkish-purple spike-like flowers.
- Flowers bloom from late June through to September.
- Square 4-sided stem, lance shaped leaves that are arranged opposite from each other.
- Grows in wet/riparian areas.
Consequences of invasion
- Forms dense stands with thick mats of roots, which degrades wetland habitats.
- Decreases biodiversity.
- Large infestations can clog irrigation canals, degrade farm lands and reduce forage values of adjacent pastures.
- The best time to remove Purple Loosestrife is June, July and early August, when flowers can be seen but before seeds have formed.
- Dispose of Purple Loosestrife by bagging and disposing at your local landfill. See our In the Garden page to learn more about proper disposal.
- Biocontrol agents are available in BC for this plant.
Purple Loosestrife | ISCBC
CKISS Downloadable Profile
Purple Loosestrife Best Management Practices | ISCMV
Purple Loosestrife | Ontario’s Invading Species Awareness Program
Manitoba Purple Loosestrife Project
Invasive Plants with Biocontrol | BC Ministry of Environment