Hesperis matronalis L.
Dame’s rocket is a native of Eurasia that has been cultivated throughout the world due to its attractive flowers. It is a biennial or short-lived perennial that can grow to 4 feet tall, although most are 2-3 feet. The leaves are alternately arranged on upright stems and are lance shaped with toothed margins, though sometimes they are entire and widest at the base. There are short hairs on the top and bottom of the leaves, giving it a rough feel. The flowers are about 2 cm across and have four petals. The flowers are generally purple, but can range from pink to white as well.
Dame’s rocket has very prolific seed production and an aggressive root system which enables it to spread quickly. Because it has such a showy flower, it is often cultivated in gardens, and from there it can spread rapidly. This allows the plant to form dense stands, which can then quickly crowd out desirable native species.
In Teton County this plant is usually found escaping from gardens and moving along ditches, roadsides, and waterways.
For help managing infestations
please call Teton County Weed & Pest District at 733-8419.