Persicaria tinctoria

Persicaria tinctoria
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Core eudicots
Order:	Caryophyllales
Family:	Polygonaceae
Genus:	Persicaria
Species:	P. tinctoria
Binomial name
Persicaria tinctoria (Aiton) H.Gross

Persicaria tinctoria (syn. Polygonum tinctorium)^[1] is a species of flowering plant in the buckwheat family. Common names include Chinese indigo. It is native to Eastern Europe and Asia.

The leaves were a source of indigo dye. It was already in use in the Western Zhou period (ca. 1045-771 B.C.), and was the most important blue dye in East Asia until the arrival of Indigofera from the south.

References