Blue Porterweed (Stachytarpheta jamaicensis, french: Verveine bleue), an invasive species. (960k)
Here are the pictures of Blue Porterweed (Stachytarpheta jamaicensis) with links to the pages on which they appear, links to the full sized picture, and the description of the picture with links to the entry in iNaturalist (inaturalist.org)
All pictures are © Dr. Günther Eichhorn, unless otherwise noted.
Congo Nature
Dr. Günther Eichhorn Travel Website
Soaring website