Their pervasive fragrance and gaudy color suggests an overdressed matron wearing too much cheap perfume, as these plants often become too much in the landscape.
Kane County Wild Plants & Natural Areas
Dick Young was referring to Dame’s Rocket (Hesperus matronalis) in bloom now along partially shaded roadsides, railroad tracks, and other waste places. Commonly called “Wild Phlox” because of its resemblance from a distance to Garden Phlox, but its 4-petaled flowers identify it as a member of the mustard family rather than the Phlox family that has 5-petaled flowers. It was introduced from Europe into American gardens in the 17th century and has since escaped cultivation. It forms large, conspicuous colonies in bloom in late May and early June. A biennial, it will flower, produce seed–lots of seed–, and die by midsummer. The seed germinates easily, producing a rosette the first year and flowers the 2nd year.
. Although it is not yet a large-scale invasive, it can spread rapidly from seed and form dense patches. Its impacts are not yet well known; in fact, it is not yet widely recognized as an invasive species in the Midwest. The U.S. Department of Agriculture has declared it a noxious weed. Three states, Connecticut, Massachusetts, and Colorado have banned it.
Does it displace native plants? The only areas where I see it growing in the wild is along country roads and railroad tracks; the native plants have long-since been displaced by other invasives. In Forest Preserves and private property, it should be prevented from going to seed by cutting the spent flowers off, which may have to be done more than once. It’s prolific seeding habit gives it the potential to be another Garlic Mustard.
Beware! Dame’s Rocket seed is frequently included in “Meadow in a Can” along with other Eurasian biennials. Avoid this altogether.