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  3. Dame's Rocket

Dame's Rocket

Hesperis matronalis

Summary 6

Hesperis matronalis is an herbaceous flowering plant species in the family Brassicaceae. It has numerous common names, including dame's rocket, damask-violet, dame's-violet, dames-wort, dame's gilliflower, night-scented gilliflower, queen's gilliflower, rogue's gilliflower, summer lilac, sweet rocket, mother-of-the-evening, Good & Plenties, and winter gilliflower.

Short Description 7

An herbaceous, biennial plant that grows up to 1m4( ft) high. The flowers are produced from May-August and bear loose clusters of attractive, fragrant, pinkish-purple to white four-petaled flowers. The leaves are alternate, slightly hairy, and lance-shaped with toothed margins. Seeds are rounded, dark reddish-brown, held in long, erect pods that ripen from June through August.

Source: EwA Invasive Pocket Fieldguide | © Earthwise Aware

Description 6

Hesperis matronalis grows 100 cm or taller, with multiple upright, hairy stems. Typically, the first year of growth produces a mound of foliage, and flowering occurs the second year; the plants are normally biennials, but a number of races can be short-lived perennials. The plants have showy blooms in early to mid spring. The leaves are alternately arranged on upright stems and lanceolate-shaped; they typically have very short petioles (or lack them) and have toothed margins, but sometimes are entire and are widest at the base. The foliage has short hairs on the top and bottom surfaces that give the leaves a somewhat rough feel. The larger leaves are around 12 cm long and over 4 cm wide. In early spring, a thick mound of low-growing foliage is produced; during flowering the lower parts of the stems are generally unbranched and denuded of foliage and the top of the blooming plant might have a few branches that end in inflorescences.

The plentiful, fragrant flowers are produced in large, showy, terminal racemes that can be 30+ cm tall and elongate as the flowers of the inflorescence bloom. When stems have both flowers and fruits, the weight sometimes causes the stems to bend. Each flower is large (2 cm across), with four petals. Flower coloration varies, with different shades of lavender and purple most common, but white, pink, and even some flowers with mixed colors exist in cultivated forms. A few different double-flowered varieties also exist. The four petals are clawed and hairless. The flowers have six stamens in two groups, the four closest to the ovary are longer than the two oppositely positioned. Stigmas are two-lobed. The four sepals are erect and form a mock tube around the claws of the petals and are also colored similarly to the petals.

Some plants may bloom until August, but warm weather greatly shortens the duration on each flower's blooming. Seeds are produced in thin fruits 5–14 cm long pods, containing two rows of seeds separated by a dimple. The fruit are terete and open by way of glabrous valves, constricted between the seeds like a pea pod. Seeds are oblong, 3–4 mm long and 1–1.5 mm wide.

In North America, Hesperis matronalis is often confused with native Phlox species that have similar large showy flower clusters. They can be distinguished from each other by foliage and flower differences: dame's rocket has alternately arranged leaves and four petals per flower, while phloxes have opposite leaves and five petals.

Invasiveness 8

Hesperis matronalis is native to southern Europe from Spain to Turkey, and has been introduced to many other parts of the world with temperate climates. H. matronalis is found in many areas of Ireland, including Belfast, as a garden escape.

Dame's rocket was brought to North America in the 17th century and has since become naturalized there, now growing throughout most of the US and Canada. The US Department of Agriculture website has a map showing states and provinces in which the plant has been found.

It is considered an invasive species in some areas. Five U.S. states have placed legal restrictions on it:

In Alberta, Canada, it is considered a noxious weed, meaning its growth or spread needs to be prevented.

🚧 Control Methods (EwA Content Development in Progress) 7

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Sources and Credits

  1. (c) Bill MacIndewar, some rights reserved (CC BY-NC), uploaded by Bill MacIndewar, https://www.inaturalist.org/observations/120430573
  2. (c) Claire O'Neill, some rights reserved (CC BY-NC), uploaded by Claire O'Neill, https://www.inaturalist.org/observations/116902877
  3. (c) Joe MacIndewar, some rights reserved (CC BY-NC), uploaded by Joe MacIndewar, https://www.inaturalist.org/observations/80032467
  4. (c) charlielow, some rights reserved (CC BY-NC), uploaded by charlielow, https://www.inaturalist.org/observations/25953476
  5. (c) mochabaz, some rights reserved (CC BY-NC), uploaded by mochabaz, https://www.inaturalist.org/observations/150947179
  6. (c) Wikipedia, some rights reserved (CC BY-SA), https://en.wikipedia.org/wiki/Hesperis_matronalis
  7. (c) Claire O'Neill, some rights reserved (CC BY-SA)
  8. Adapted by Claire O'Neill from a work by (c) Wikipedia, some rights reserved (CC BY-SA), https://en.wikipedia.org/wiki/Hesperis_matronalis

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