Louis Prat, one of the firm's owners, noticed that Joseph had artistic talent and convinced his father to let him be enrolled at the École supérieure des beaux-arts de Marseille [fr].
Until 1905, he benefitted greatly from the patronage of Baron Alphonse de Rothschild, who bought his paintings and donated them to provincial museums.
In 1906, he exhibited landscapes at the Exposition coloniale de Marseille [fr] and was awarded a travel grant to Tunisia the following year.
For the remainder of his career, he received significant support from his friends Étienne Martin, José Silbert and Édouard Crémieux who were, successively, the Directors of the Association des Artistes Marseillais.
Two major retrospectives have been held: Les terres marines de Joseph Garibaldi at Cassis in 2006, and Joseph Garibaldi, le Midi paisible at the Palais des Arts [fr] of Marseille in 2012.