Wildflowers of Toronto's High Park​​

Loosestrife, purple
​Lythrum salicaria

​Family: Loosestrife
Introduced and invasive

Blooms: July to September
Habitat: Marshes and wet places

Height: up to 1.5 m

​Flowers: 15-20 mm in 10-40 cm spike clusters/

This plant forms large colonies, excluding native wildflowers.  It produces abundant seeds and has no natural predators in North America. 

It was pervasive in High Park but, since 2003, has been brought under control by the imported black-margined loosestrife beetle (galerucella calmariensis) which eats the leaves and new shoot growth.