Lychnis is a genus of flowering plants that belongs to the family Caryophyllaceae. They are commonly known as "catchfly" because of the sticky sap that covers their stems and leaves. Lychnis plants are native to Europe, Asia, and North America, and are now grown in many other parts of the world as ornamental plants.

Lychnis plants have upright stems that can reach up to two feet in height. The flowers are typically pink, red, or white, and are arranged in clusters. The foliage of Lychnis plants is often green and can be quite ornamental, with lance-shaped leaves.