The silk factory where he worked was destroyed during the Siege of Lyon (1793), prompting him to move to Paris, where he lived in poverty for several years. After eventually returning to Lyon, he worked for a embroidery workshop before being appointed professor of flower painting at the École des Beaux-Arts in Lyon, a position he held until 1823, when he was succeeded by Augustin Alexandre Thierriat.
Overlooked by his contemporaries, Berjon remained in Lyon, living on a municipal pension and continuing to paint, even though his work was no longer exhibited. His hot temper earned him many enemies, and his death went largely unnoticed in the press.
He exhibited at the Paris Salon multiple times, notably in 1791, 1798, 1799, 1804, 1810, 1817, 1819, and 1842. In 1819, he was awarded a silver medal. In 1796, he presented in Paris an engraving created using a technique he invented himself.
In addition to still lifes featuring flowers, fruits, and miniatures rendered in oil or pastel, Berjon left behind a significant collection of watercolors, ink washes, and chalk drawings on tinted paper. He was also recognized as a portraitist and painted numerous animals, floral designs for textiles and decorations, as well as costume designs for the theater. The majority of his work is preserved in Lyon. A remarkable sepia portrait of a man, attributed to him, was showcased in a retrospective dedicated to his work in Lyon in 1904.