Appeal: Monkshood has dark green lobed leaves and forms purple/blue flowers on top of its upright stems. Interesting flowers that form an almost hood like structure on top said to resemble a monks hood, hence its common name. All parts of this plant are poisonous and used to be used to poison arrow tips for hunting. Monkshood is a beautiful perennial to add to the garden where you want to add height and purple color. Deer resistant.