Centranthus is a genus of nine Mediterranean species. One species (Centranthus ruber) is widely cultivated as a border plant outside its native distribution range. Centranthus calcitrapae (L.) Dufresne is a weedy species in southern Europe. It is sometimes introduced in Belgium as a weed in containers with olive trees in nurseries (Hoste & al. 2009). Centranthus angustifolia (Mill.) DC. is extending its native range in France and has reached by now Lorraine (SW of Nancy), relatively close to the Belgian borders (see Lambinon & al. 2004 for their distinction). One day, it may occur in Belgium as well.
Literature
Hoste I., Verloove F., Nagels C., Andriessen L. & Lambinon J. (2009) De adventievenflora van in België ingevoerde mediterrane containerplanten. Dumortiera 97: 1-16.
Jäger E.J., Ebel F., Hanelt P. & Müller G. (eds.) (2008) Rothmaler Band 5. Exkursionsflora von Deutschland. Krautige Zier- und Nutzpflanzen. Springer Verlag, Berlin: 880 p.
Lambinon J., Delvosalle L., Duvigneaud J. (avec coll. Geerinck D., Lebeau J., Schumacker R. & Vannerom H. (2004) Nouvelle Flore de la Belgique, du Grand-Duché de Luxembourg, du Nord de la France et des Régions voisines (Ptéridophytes et Spermatophytes). Cinquième édition. Jardin botanique national de Belgique, Meise: CXXX + 1167 p.
Richardson I.B.K. (1976) A revision of the genus Centranthus DC. (Valerianaceae). Bot. J. Linn. Soc. 71: 211-234.