Common Name: Dame's Rocket
Scientific Name: Hesperis matronalis
Habitat: roadsides, forest edges, ornamental beds
Provincial Designation: Noxious
Noxious weeds are plant species designated in the Alberta Weed Control Act. Noxious weeds must be controlled, meaning their growth or spread needs to be prevented.
Dame's rocket is native to Europe and southwest Asia and was introduced to North America as an ornamental flower.
It is a prolific seed producer that can quickly form dense stands in moist, shaded grassland areas and along woodland edges.
This plant grows up to 1 m tall and is often branched near the top. Its flowers are fragrant, 8-15 mm wide, white or pink in colour, and have four petals each.
The alternately arranged leaves are elliptic or lance-shaped, 4-20 cm long and 2-10 cm wide, and have toothed edges. The leaves and stems are covered in hairs. The seed pods of this plant are distinctively long and narrow, 5-10 cm long and 2-2.5 mm wide.
This is a biennial plant. In the first year of growth, it produces a rosette - a circle of leaves straight from the ground. In the second year, it grows a flowering stalk.
Can Be Confused With ...
Garden Phlox - Phlox paniculata -phlox has 5 petals and opposite leaves, but Dame’s rocket has 4 petals & alternate leaves. Garden phlox is an ornamental garden plant and fine for you to grow!
Learn more about this species:
See Fact Sheet - Alberta Invasive Species Council