It's the closest thing in the natural world to spray-painting. One minute, the chair of the parks committee has the idea of entering your town for a Britain in Bloom award, and the next minute, every roundabout and lamp standard is gaudy with petunias. They tumble from containers and carpet whole tracts of land with wall-to-wall petals. And at the end of the summer, they will disappear as instantly as they came, to be replaced just a few short weeks later by Christmas decorations.
But although these rent-a-blooms might seem a product of our modern, throw-away society, their roots are firmly planted in Victorian soil. The invention of sheet glass in 1833 and the removal of the glass tax a few years later led to the springing up of greenhouses, where seedlings could be nurtured ready to be bedded out en-masse. And as for the plants themselves, they were also very much the product of scientific advance.
It was in the mid-18th century that collectors first came upon the white Petunia axillaris and purple Petunia violacea growing wild in South America. These lank, small-flowered members of the Solanaceae, or nightshade, family (relatives include tomatoes, potatoes and peppers), were unexciting by today's standards. But in the early years of the 19th century, European growers began crossing the two species in search of larger flowers and more colours, with tantalising results.
Occasionally, double flowers or fringed single flowers would emerge. So to master the apparently random production of these spectacular blooms, growers began to apply the principles of inheritance as outlined in 1865 by pioneering geneticist Gregor Mendel.
But not until 1934 did the Sakata Seed Corporation in Japan manage to create the first consistently fully-double petunias, in a mix the company called "All Double Victorious". But the queen of bedding plants didn't rest there. Today's petunias come in every shape, size and colour. Indeed, in the early 1980s, it was a petunia containing a gene from a bacterium that became the very first genetically modified plant. Can the spray-on bloom be very far away?