People began practicing window box gardening as long ago as ancient Rome.
In the first century B.C., before the height of the Roman empire, nearly all Romans cultivated their own small cottage gardens for practical purposes: to provide food, medicinal herbs, and flowers for rituals.
Among the lower classes, in small villas where peasants had little gardening space, many people grew the plants they needed in window boxes.
Roman wives and mothers, to whom the care of the essential family herb garden was entrusted, may have kept herb window boxes for medicines and cooking. The Romans also grew many different kinds of flowers in their window boxes, originally harvested for ritual use, and later grown for decoration.
They loved lilies, violets, pansies, hyacinths, and irises, but roses were ever their favorite, and they cultivated many kinds. Pliny the Elder, an ancient Roman natural philosopher, was said to have reminisced about the days when the villagers' windows were brimming with colorful window boxes, before crime in Rome became such a widespread problem that it forced them to shut their windows and deprive passersby of their beauty.
Window boxes later gained such popularity among the rich upper classes that wealthy people began developing balcony and rooftop gardens that eventually became extremely elaborate, overflowing with flowers and trailing vines, shrubs, small trees, and even fish ponds. As the focus of gardening moved from survival to pleasure and art, the rich created the formal Roman gardens with rolling lawns, fountains, and marble statues that remind us of classical Rome today. Yet, humble window boxes always maintained their popularity, and to this day, the second- and third-story windows of many Italian villas still have window boxes brimming with color.
Window boxes spread with the Romans throughout Europe to England, France, Ireland,Germany, and Holland.
The window box itself evolved from its original Roman terra cotta form into new varieties, such as wire hay baskets found in English cottage gardens, and the elegant wrought iron window boxes of France. Window boxes later spread to America, where they adorned colonial homes. Over time, Americans lost interest, tending more towards wide lawns and shrubberies.