Dame's Rocket

I mark the seasons by what's blooming - the daffodils and tulips are a memory. The poppies have mostly faded. A few lilacs remain, but the dominant flower by the roadsides is Dame's Rocket. In a few weeks, the daylillies will be everywhere. Right now in gardens it's iris.

What is Dame's Rocket? According to Wikipedia:

Dame's Rocket, also known as Dame's Violet, Dames-wort, Sweet Rocket, and Mother-of-the-evening (Hesperis matronalis) is a herbaceous perennial plant belonging to the mustard family, Brassicaceae. A native of Eurasia once cultivated and enjoyed as a traditional garden plant, Dame's Rocket was brought to North America in the 1600s and has since become naturalized there; it is considered an invasive species in some areas.

The plant is often confused with look-alike native phlox species in North America, but the former can be easily identified by its alternate (rather than opposite), toothed lanceolate leaves (5-15 centimetres in length, larger towards the base of the plant) and showy flowers, which have four rather than a phlox's five petals.

Reaching a maximum height of one metre (3 feet), Dame's Rocket shoots up quickly in spring and enters full bloom by May. The plentiful flowers, in elongate clusters atop strong hairy stalks, are large (2 cm) and vary in colour from white to lavender purple, some being a variegated intermediate between the two. A double-flowered variety is known. The flowers are also highly fragrant; the genus name Hesperis is Greek for evening, a reference to this plant's sweet aroma becoming evermore conspicuous towards evening. Much more available on the subject here.