The characteristic purplish-red colour of the flowers or leaves of these plants.
A red to purple azo dye used as a biological stain, and in some countries in cosmetics and as a food colouring.
Any of various herbs of the genus Amaranthus.
The seed of these plants, used as a cereal.
An annual plant, Polygonum aviculare, found in fields and wasteland
Paspalum distichum, a weedy perennial grass of wet areas