05/24/2026
May is Invasive Species Awareness Month in Illinois. In recognition CLPD is spotlighting Dames Rocket (Hesperis matronalis), a showy plant often introduced in residential landscaping, which thrives primarily in woodland habitats but also open areas.
Dame’s rocket is native to parts of Europe and Asia. In the United States, absent natural controls such as disease and insects found in its home range, it can aggressively take over natural areas. Often displacing and outcompeting a significant amount of the native vegetation that indigenous species have adapted to depend on. Unlike the native Phlox, which has 5 petaled flowers, Dame’s Rocket has 4 petals and being in the mustard family, it develops seed pods that produce an impressive 20,000 to 30,000 seeds per plant.
For more information on Dame’s Rocket, its invasive potential and similar looking native alternatives such as Phlox that can be planted instead, see the following links:
https://dnr.wisconsin.gov/topic/Invasives/fact/DamesRocket
https://chicagolivingcorridors.org/resources/creating-native-habitat/invasive-plants/dames-rocket-hesperis-matronalis/
