Wall-climbing greenery is a term used to describe plants such as IVY (3 letters) that are able to climb up walls and other vertical surfaces. These plants are often used to add a decorative touch to the exterior of buildings, as well as providing a natural way to insulate and protect the walls from the elements. IVY is one of the most popular wall-climbing plants, due to its hardiness and ability to thrive in a variety of climates.