Known as the vesper iris, the flowers of this plant open at 4:00 pm each day, just in time for evening vespers. This is a collector’s plant; something special for those who like growing plants that none of their gardening buddies have. Although fairly rare in cultivation, the vesper iris is easy to grow and adds a special touch to the garden late in the year when few other plants flower. It flowers for many weeks with each flower remaining open for one day. A well grown plant can have over a hundred flowers.