- a name given to various plants, especially the rose of Sharon
- ‘I was considering growing Hypericum calycinum (Aaron's Beard) under/in front of my azaleas after reading about them in a book on gardening in the Mid-Atlantic.’
- ‘Plants such as winter creeper and Aaron's beard may become rangy and untidy.’
- ‘Aaron's beard does well in full sun to partial shade, and tolerates almost complete shade.’
Early 19th century: alluding to Aaron, whose beard “went down to the skirts of his garments” (Psalms 133:2), because of the prominent hairy stamens or the long runners that some of these plants put out.