Cunningham's Encyclopedia of Magical Herbs - Scott Cunningham 1985
Knotweed
The Herbs
(Polygonum aviculare)
Folk Names: Armstrong, Centinode, Cowgrass, Hogweed, Knotgrass, Nine Joints, Ninety Knot, Pigrush, Pigweed, Red Robin, Sparrow’s Tongue, Swynel Grass
Gender: Feminine
Planet: Saturn
Element: Earth
Powers: Binding, Health
Magical Uses: To “bind” woes and miseries, hold some knotweed in your hand. Pour your problems into the herb; see it absorbing them and then burn it. When carried, knotweed strengthens and protects the eyes.