Wikipedia: Flower power was a slogan used during the late 1960s and early 1970s as a symbol of passive resistance and non-violence ideology. It is rooted in the opposition movement to the Vietnam War. The expression was coined by the American beat poet Allen Ginsberg in 1965 as a means to transform war protests into peaceful affirmative spectacles. Hippies embraced the symbolism by dressing in clothing with embroidered flowers and vibrant colors, wearing flowers in their hair, and distributing flowers to the public, becoming known as flower children.
Flower Power could also be used for the environment. 🙂