Ceratostigma plumbaginoides Bunge
Plumbago larpentiae Lindl.
Blue Plumbago, Leadwort
Blue plumbago is native to western China. It is not found in the wild in North America. “Plumbago,” from the Latin plumbum, for lead, refers to the blue flower color of these plants; so does “leadwort.” A mineral sometimes called blue lead ore, also known as galena, is the namesake. (It is a little confusing though, since galena is a very shiny, dark silver color. The blue color comes from a layer of oxidation that sometimes forms on the surface, but I couldn’t find any very convincing photos of this.)
Identification: Plants are 6-12" (15-30 cm) high and about 12-18" (30-45 cm) around, forming mats and often used by gardeners as ground covers. Leaves are oval and shiny, up to 2" (5 cm) long, turning bronze red in the fall. Bright gentian blue 5-petaled flowers, each ½-¾" (1.3-1.9 cm) around, appear in clusters from July to September.
Ceratostigma plumbaginoides at Cornell University’s Gardening Guide
Ceratostigma plumbaginoides on eFloras
Ceratostigma plumbaginoides on CalPhotos
Ceratostigma plumbaginoides in Paghat's Garden
Ceratostigma plumbaginoides on fossilflowers.org
Ceratostigma plumbaginoides description by Thomas H. Kent, last updated 25 May 2020.
Range: Zones 5-9: