Spike, as it is usually called, is a dramatic plant that has leaves shaped like swords. The leaves are sharp and require gloves when they are being handled. Spike is an evergreen plant that is used for its foliage, not its flower. This plant is very low maintenance. Spike is heat tolerant. It can add vertical interest if planted in a mixed border. While Spike is a perennial in warmer climates, it is considered an annual in climates with freezing winters.