Plumbago is a genus of 10-20 species of flowering plants in the family Plumbaginaceae. Plumbago and leadwort (names which are also used by the genus Ceratostigma) are the most popular common names.
The species include herbaceous plants and shrubs which grow to 0.5-2 m tall. The leaves are arranged spirally, simple, entire, 0.5-12 cm long, have a tapered base and often a hairy margin. Flowers can be white, blue, purple, red, or pink, with a tubular corolla and with five petal-like lobes; they are produced in racemes.
The flower calyx has glandular hairs, which secrete a sticky mucilage that is capable of trapping and killing insects. The purpose of this secretion is not clear.
The name Plumbago is derived from Latin plumbum ("lead"), either from the lead-blue flower colour of some species (OED), or from the plant at one time being a supposed cure for lead poisoning (Huxley 1992).
Native to warm temperate to tropical regions of the world.
|Standard Cyclopedia of Horticulture|
Plumbago (from Latin for lead, from the lead- colored flowers of some species, or because of some old tradition). Plumbaginaceae. Leadwort. Subshrubs or herbs, often cultivated, particularly under glass, for the handsome phlox-like flowers. Mostly perennial, sometimes climbing, often more or less woody: lvs. usually alternate and entire, clasping (or auricled) by the blade or by base of petiole: fls.
spicate or racemose on the ends of the branches, blue, violet, red, or white, gamopetalous, salverform, the tube usually slender; calyx tubular, 5-toothed, and somewhat angled, glandular; stamens usually 5. free from the corolla-tube, the filaments mostly with a dilated base; ovary attenuated at the top, the single style with 5 stigmas: fr. a membranaceous 5-valved caps.— About 10 or a dozen species in- habiting warm countries, chiefly of Eu., Asia, and Afr. For P. Larpentae, consult Ceratostigma.
Two species of shrubby plumbagos, P. capensis and P. rosea, are deservedly well known. In the middle and northern states they are treated as greenhouse pot-plants and are usually turned out to flower in summer. They are readily prop, by cuttings taken either in autumn from plants growing in the open or in the spring from stock plants. They require an intermediate temperature. CH
Pests and diseases
- Selected species
- Plumbago aphylla Bojer ex Boiss. Madagascar region.
- Plumbago auriculata Lam. (syn. P. capensis). Cape Leadwort. South Africa.
- Plumbago caerulea Humboldt, Bonpl. & Kunth (syn. P. coerulea). Western South America (northern Chile to Colombia).
- Plumbago europaea L. Common Leadwort. Mediterranean region to central Asia.
- Plumbago indica L. (syn. P. rosea). Southeast Asia.
- Plumbago pulchella Boiss. Mexico.
- Plumbago scandens L. Summer Snow Leadwort. Southern United States south to northern South America; sometimes included in P. zeylanica.
- Plumbago wissii
- Plumbago zeylanica L. ‘ilie‘e (Hawaiian islands) Southeast Asia south to Australia and into Pacific.
- Germplasm Resources Information Network: Plumbago
- Flora of Chile: Plumbago (pdf file)
- Flora Europaea: Plumbago
- Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan.
- Schlauer, J. (1997). "New" data relating to the evolution and phylogeny of some carnivorous plant families. Carnivorous Plant Newsletter 26(2): 34-38 (available online).