The use of flowers to symbolize emotions or messages, like strong love, courage, and beauty, was popularized in the Victorian era, though flowers have been used as symbols since ancient times. Flower species and color typically both play a role in their meanings, and there are multiple flowers for each feeling you may want to convey, depending on the tradition you follow.
According to the Victorian Language of Flowers guide, red flowers indicate a strong love and passion, which is why red roses are so commonly given as gifts of romance in Western cultures. Red carnations can also be used to symbolize a strong, aching love, while pink carnations represent a strong mother's love, referencing a Biblical story where the mother of Jesus cried tears that became pink flowers. Pansies of all colors were used in Victorian times to indicate a forbidden love. Tulips, especially red varieties, are also a sign of love, and, in Turkey, they were once a common ingredient for love potions.
The king protea is a flower strongly associate with courage, as it represents transformation and the willingness to be daring and resourceful. In China, the plum blossom is used to symbolize courage, especially around the Chinese New Year.
Lilies were symbolical of Venus, the Roman goddess of beauty, in ancient times, and have since become more strongly associated with heavenly or pure emotions or a more refined beauty. Today, the amaryllis is used to symbolize "splendid beauty," and lavender-colored heather is used to symbolize solitude and beauty. Orchids are often used to symbolize exotic beauty.