Born in the Frisian Sint Jacobi parish, Germ de Jong moved to Amsterdam at the age of four. Although De Jong dreams of a career as a painter, inspired by the famous painters of the Eighties led by Breitner, his father has other plans and he is put to work in a factory. In the meantime, he secretly takes the entrance exam for the Applied Arts School Quellinus Amsterdam. To earn a living, he has all kinds of jobs. He also registers at the National Academy of Arts and the academies in Rotterdam and The Hague. He doesn't stay at any school for long, he prefers to go out and enjoy life to the fullest. After he had a successful first solo exhibition at art dealership Herman d'Audretsch in Amsterdam in 1918 and won the Willink van Collen encouragement prize for young artists, his name was definitively established. He travels with his wife to Paris, where it happened at that time. He meets Piet Mondriaan and Conrad Kickert and Picasso is his neighbor. Initially, De Jong mainly painted landscapes in a dark palette. In Paris his work becomes strong, striking, and above all colourful. He prefers to paint cityscapes, which, in their preference for straight blocks of houses, fences and blank walls, reveal the pursuit of a certain abstract order.
Due to marital problems, the family returned to the Netherlands in 1933, where they settled in Schoorl near Bergen. There De Jong came into contact with the painters of the Bergen School. From that time on he mainly occupied himself with what can safely be called his specialty: the flower still life. They are often colourful bouquets set up in a spontaneous brushstroke in full, blooming colours. They provided him with recognition and publicity and in 1956 a retrospective exhibition in the Stedelijk Museum in Amsterdam. But his second marriage also did not last and was dissolved in 1936. During the Second World War he met his third wife and they found a home in Amsterdam. The Frisian native usually spends his summers on Ameland, at Hotel Hofker in Nes.
After the Second World War, De Jong's work reveals, in addition to influence from his Bergen and Paris period, also influence from the travels he made to Morocco, Spain, Italy and Corsica. De Jong was a bohemian who led an lavish lifestyle and died a poor artist.