This section is from the book "The Botanical Magazine; Or, Flower-Garden Displayed", by William Curtis. Also available from Amazon: The Botanical Magazine; or, Flower-Garden Displayed, Volume I.
Convolvulus Nil. Azure Convolvulus.
Cor. Campanulata, plicata. Stigmata 2. Caps. 2-locularis: loculis dispermis.
CONVOLVULUS Nil foliis cordatis trilobis, corollis semiquinquefidis, pedunculis petiolo brevioribus. Linn. Syst. Veg. ed. 14. Murr. p. 209. Ait. Hort. Kew. v. 1. p. 209.
CONVOLVULUS caeruleus hederaceo anguloso folio. Bauh. Pin. p. 295.
NIL Arab. Gef. hor. Eyst.
CONVOLVULUS Caeruleus. Blew Bindweed. Ger. Herb. p. 715. cum ic.
CONVOLVULUS trifolius five hederaceus purpureus. The greater purple Bindeweede or Bell-Flower with cornered leaves. Park. Parad. Pl. 361. fig. 2.
All our writers on exotic botany treat of this plant, Gerard, one of the first, gives us the following account: "This beautiful Bindweed, which we call Convolvulus Caeruleus, is called of the Arabians Nil: of Serapio, Hab al nil, about Alepo and Tripolis in Syria, the inhabitants call it Hasmisen, the Italians Campana azurea, of the beautifull azured flowers and also Fior de notte, bicause his beautie appeereth most in the night:" he informs us, that it grew in his garden, but perished before it ripened its seeds. Parkinson says, it thrives remarkably well in our country, if the year be any thing kindly: Miller informs us, that it is a native of Africa and America, extols it as one of the most beautiful of the genus, observes, that it is a very distinct species from the purpurea, of which it has been considered by some as a variety; that it will grow to the height of eight or ten feet, that in favourable seasons the seeds will ripen in the open air, and that it requires the same treatment as other annuals usually raised on a hot-bed. Mr. Aiton considers it as a stove plant, as indeed most of our tender annuals properly are.
It flowers from July to September.
Though apparently common in our gardens formerly, it is now very rarely met with.