This chemical is often mentioned in the context of anti-depressants, but research on monkeys in the twentieth century made it clear that the good feeling of serotonin is released when a mammal advances its social importance. Flowers can help you do that. Whether you grow them, buy them, or admire them from a distance, flowers can stimulate the sense of pride that your mammal brain is looking for.
No one likes to admit they care about social importance, but if you fail to stimulate your serotonin, you end up feeling bad. This is why we’re always looking for socially acceptable ways to trigger it. Many of our social rituals exist to satisfy this natural urge in a healthy way. Flowers support these rituals. Whether you give them, receive them, or buy them for yourself, flowers help you feel important in ways that do no harm.