Purple Loosestrife

Purple Loosestife Control Guide

The purple loosestrife is an erect perennial with opposite or whorled leaves, its thick taproot supports up to 50 stems that can reach a height of 6 feet. The purple loosestrife is an aquatic to semiaquatic plant with a distinctive purple flower that makes it easy to recognize. This invasive plant thrives in marshes, wet meadows, streams, river banks, lake shores, and ditches. It can also survive in drier conditions.


The purple loosestrife extended flowering season allows it to produce vast quantities of seed that can easily spread to large areas. Early management to avoid large invasions is the best prevention.

Physical/Mechanical Control

Small infestations with younger plants (1-2 years old) can be hand-pulled. Plants more than 2 years old should be dug out with special care, their entire root system must be removed from the ground; all plant material should be bagged and disposed of. Mowing is not recommended because it will contribute to seed dispersal and seed bank exposure if the mower scrapes the soil. Physical removal, when used in conjunction with chemical control methods, will maximize success.

Chemical Control

Clearcast Herbicide and MSO Adjuvant are specifically designed for use in and around water.  These products are the ultimate solution in eliminating most emergent vegetation for long-lasting results with minimal retreatment.