wallflower

Perennial plant native to southern Europe, bearing fragrant yellow and orange flowers. The name is derived from the fact that the plant, when naturalized to a region, is often found growing out of the nooks and crannies in an old wall, or a cliff. The natural tendency for this plant to separate itself from the other denizens of a formal garden, and grow in isolated locations, doubtless led to the use of the term "wallflower" to describe an anti-social, or shy individual, who lingers in the background, against the wall, as it were, at social occasions.