Saying it with flowers has been an industry standard for those who sell that product, but art photographers and painters have known for many years that any flower has plenty to say to people. Each plant struggles to survive and grow, and they then present the world with their beauty. It takes a good eye to capture that beauty forever in a painting or photo, but it is becoming more common of late. People have learned to recognize this is art they can enjoy for many years.
For plants, a flower is nothing more than a way to attract birds or bees to spread their pollen. Each delicate blossom says something about the plant, and nature has given them the ability to use it as a display that humans can also enjoy. While many people think of these blossoms as a non-permanent fixture, mankind has methods to preserve this beauty over time. Pictures and paintings stand the test of time, so it gives flowers a way to continue attracting admirers long after they have gone to seed.
The art of pictures varies with cultures. Japanese flower art is about displaying the whole plant, and it is a simpler display than a Western one would be. Many photographs from Western cultures will capture an entire field of flowers, but individual blossoms are becoming more popular as people use them to decorate the walls of their homes. Some people may take their own photos, or they have found them online for sale.
Paintings on flowers have often been combined with other action in the past, but artists have learned people want individual plants in collections. This used to be considered more of a folk art, but it is becoming a mainstream trend as more people recognize the beauty within a single flower that is properly displayed.