Ruivinha (Rubia peregrina var. angustifolia)
Perennial madder plant whose roots Madeirans used to dye cloth red and which was recommended against rickets.
A perennial plant of the family Rubiaceae, with rough linear-lanceolate or sublinear leaves and small flowers arranged in axillary cymes. Its roots are widely used in dyeing. When Madeirans wish to use them, they usually wash them first and then pound them with unripe blackberries. If the mixture is boiled together with the cloth to be dyed, the cloth takes on a beautiful red colour; it should then be boiled again with ash so that the colour does not fade.
The roots of the ruivinha are recommended for rickets, and they have the property of dyeing red the bones of people who take them internally.